Revert CMake: Make most target symbols hidden by default

This reverts r362990 (git commit 374571301dc8e9bc9fdd1d70f86015de198673bd)

This was causing linker warnings on Darwin:

ld: warning: direct access in function 'llvm::initializeEvexToVexInstPassPass(llvm::PassRegistry&)'
from file '../../lib/libLLVMX86CodeGen.a(X86EvexToVex.cpp.o)' to global weak symbol
'void std::__1::__call_once_proxy<std::__1::tuple<void* (&)(llvm::PassRegistry&),
std::__1::reference_wrapper<llvm::PassRegistry>&&> >(void*)' from file '../../lib/libLLVMCore.a(Verifier.cpp.o)'
means the weak symbol cannot be overridden at runtime. This was likely caused by different translation
units being compiled with different visibility settings.

llvm-svn: 363028
diff --git a/llvm/lib/Target/PowerPC/AsmParser/PPCAsmParser.cpp b/llvm/lib/Target/PowerPC/AsmParser/PPCAsmParser.cpp
index 094ee5a..c9524da 100644
--- a/llvm/lib/Target/PowerPC/AsmParser/PPCAsmParser.cpp
+++ b/llvm/lib/Target/PowerPC/AsmParser/PPCAsmParser.cpp
@@ -1786,7 +1786,7 @@
 
 
 /// Force static initialization.
-extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCAsmParser() {
+extern "C" void LLVMInitializePowerPCAsmParser() {
   RegisterMCAsmParser<PPCAsmParser> A(getThePPC32Target());
   RegisterMCAsmParser<PPCAsmParser> B(getThePPC64Target());
   RegisterMCAsmParser<PPCAsmParser> C(getThePPC64LETarget());
diff --git a/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp b/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp
index d848b02..4814529 100644
--- a/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp
+++ b/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp
@@ -51,7 +51,7 @@
   return new PPCDisassembler(STI, Ctx, /*IsLittleEndian=*/true);
 }
 
-extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCDisassembler() {
+extern "C" void LLVMInitializePowerPCDisassembler() {
   // Register the disassembler for each target.
   TargetRegistry::RegisterMCDisassembler(getThePPC32Target(),
                                          createPPCDisassembler);
diff --git a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.cpp b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.cpp
index 9f4cd6e..395b423 100644
--- a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.cpp
+++ b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.cpp
@@ -260,7 +260,7 @@
   return new PPCInstPrinter(MAI, MII, MRI, T);
 }
 
-extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCTargetMC() {
+extern "C" void LLVMInitializePowerPCTargetMC() {
   for (Target *T :
        {&getThePPC32Target(), &getThePPC64Target(), &getThePPC64LETarget()}) {
     // Register the MC asm info.
diff --git a/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp b/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
index f8a892d..8ba21d7c 100644
--- a/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
+++ b/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
@@ -1651,7 +1651,7 @@
 }
 
 // Force static initialization.
-extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCAsmPrinter() {
+extern "C" void LLVMInitializePowerPCAsmPrinter() {
   TargetRegistry::RegisterAsmPrinter(getThePPC32Target(),
                                      createPPCAsmPrinterPass);
   TargetRegistry::RegisterAsmPrinter(getThePPC64Target(),
diff --git a/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp b/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
index bc6c3b7..da1121b 100644
--- a/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
+++ b/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
@@ -94,7 +94,7 @@
   ReduceCRLogical("ppc-reduce-cr-logicals",
                   cl::desc("Expand eligible cr-logical binary ops to branches"),
                   cl::init(false), cl::Hidden);
-extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCTarget() {
+extern "C" void LLVMInitializePowerPCTarget() {
   // Register the targets
   RegisterTargetMachine<PPCTargetMachine> A(getThePPC32Target());
   RegisterTargetMachine<PPCTargetMachine> B(getThePPC64Target());
diff --git a/llvm/lib/Target/PowerPC/TargetInfo/PowerPCTargetInfo.cpp b/llvm/lib/Target/PowerPC/TargetInfo/PowerPCTargetInfo.cpp
index 649bd64..99b5dec 100644
--- a/llvm/lib/Target/PowerPC/TargetInfo/PowerPCTargetInfo.cpp
+++ b/llvm/lib/Target/PowerPC/TargetInfo/PowerPCTargetInfo.cpp
@@ -23,7 +23,7 @@
   return ThePPC64LETarget;
 }
 
-extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCTargetInfo() {
+extern "C" void LLVMInitializePowerPCTargetInfo() {
   RegisterTarget<Triple::ppc, /*HasJIT=*/true> X(getThePPC32Target(), "ppc32",
                                                  "PowerPC 32", "PPC");