Revert "[Target] Implement the ".rdata" MIPS assembly directive."

This reverts commit r305949 and r305950 as they didn't have the
correct commit message.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305973 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed