X86: Clean up pass initialization

Summary:
- Remove redundant initializations from pass constructors that were
  already being initialized by LLVMInitializeX86Target().

- Add initialization function for the FPS pass.

Reviewers: craig.topper

Reviewed By: craig.topper

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63218

llvm-svn: 363221
diff --git a/llvm/lib/Target/X86/X86SpeculativeLoadHardening.cpp b/llvm/lib/Target/X86/X86SpeculativeLoadHardening.cpp
index 02f07d8..40f5dbe 100644
--- a/llvm/lib/Target/X86/X86SpeculativeLoadHardening.cpp
+++ b/llvm/lib/Target/X86/X86SpeculativeLoadHardening.cpp
@@ -122,10 +122,7 @@
 
 class X86SpeculativeLoadHardeningPass : public MachineFunctionPass {
 public:
-  X86SpeculativeLoadHardeningPass() : MachineFunctionPass(ID) {
-    initializeX86SpeculativeLoadHardeningPassPass(
-        *PassRegistry::getPassRegistry());
-  }
+  X86SpeculativeLoadHardeningPass() : MachineFunctionPass(ID) { }
 
   StringRef getPassName() const override {
     return "X86 speculative load hardening";