Rename variables in gc_relocate related functions to follow LLVM's naming conventions.

Summary:
This patch is to rename some variables to CamelCase in gc_relocate
related functions. There is no functionality change.

Patch by Chen Li!

Reviewers: reames, AndyAyers, sanjoy

Reviewed By: sanjoy

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9681

llvm-svn: 237069