[PowerPC][NFC] Use -mtriple in RUN line, remove target triple in tls.ll
[PowerPC][NFC] Use -mtriple in RUN line, remove target triple in tls.ll

To avoid confusion, especially when -mtriple are also added for PPC32.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@370427 91177308-0d34-0410-b5e6-96231b3b80d8

GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm