Give MCRegisterInfo an implementation file.

Move some functions from MCRegisterInfo.h that don't need to be inline.

This shrinks llc by 8K.

llvm-svn: 160865
diff --git a/llvm/lib/MC/CMakeLists.txt b/llvm/lib/MC/CMakeLists.txt
index f11e686..99bff96 100644
--- a/llvm/lib/MC/CMakeLists.txt
+++ b/llvm/lib/MC/CMakeLists.txt
@@ -28,6 +28,7 @@
   MCObjectStreamer.cpp
   MCObjectWriter.cpp
   MCPureStreamer.cpp
+  MCRegisterInfo.cpp
   MCSection.cpp
   MCSectionCOFF.cpp
   MCSectionELF.cpp