[X86][Mips] Remove unused method declaration from the X86 and Mips AsmPrinters.

Both had a declaration of EmitXRayTable, but there is no method defined in either with that name. There is a emitXRayTable in the base class with a lower case 'e' and they both call that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320213 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed