[RABasic] Properly initialize the pass

Use the initializeXXX method to initialize the RABasic pass in the
pipeline. This enables us to take advantage of the .mir infrastructure.

llvm-svn: 304602
diff --git a/llvm/lib/CodeGen/CodeGen.cpp b/llvm/lib/CodeGen/CodeGen.cpp
index 4d30c65..256a0c9 100644
--- a/llvm/lib/CodeGen/CodeGen.cpp
+++ b/llvm/lib/CodeGen/CodeGen.cpp
@@ -77,6 +77,7 @@
   initializePostRASchedulerPass(Registry);
   initializePreISelIntrinsicLoweringLegacyPassPass(Registry);
   initializeProcessImplicitDefsPass(Registry);
+  initializeRABasicPass(Registry);
   initializeRAGreedyPass(Registry);
   initializeRegisterCoalescerPass(Registry);
   initializeRenameIndependentSubregsPass(Registry);