Restructure the propagation of -fPIC/-fPIE.

The PIC and PIE levels are not independent. In fact, if PIE is defined
it is always the same as PIC.

This is clear in the driver where ParsePICArgs returns a PIC level and
a IsPIE boolean. Unfortunately that is currently lost and we pass two
redundant levels down the pipeline.

This patch keeps a bool and a PIC level all the way down to codegen.

llvm-svn: 273566
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index a8abe72..5077727 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -480,11 +480,8 @@
   if (uint32_t PLevel = Context.getLangOpts().PICLevel) {
     assert(PLevel < 3 && "Invalid PIC Level");
     getModule().setPICLevel(static_cast<llvm::PICLevel::Level>(PLevel));
-  }
-
-  if (uint32_t PLevel = Context.getLangOpts().PIELevel) {
-    assert(PLevel < 3 && "Invalid PIE Level");
-    getModule().setPIELevel(static_cast<llvm::PIELevel::Level>(PLevel));
+    if (Context.getLangOpts().PIE)
+      getModule().setPIELevel(static_cast<llvm::PIELevel::Level>(PLevel));
   }
 
   SimplifyPersonality();