Make the test case from r329552 more portable
Make the test case from r329552 more portable

- when tuning for SCE debugger (default for ps4 targets), we will not emit
  the DW_AT_linkage_name, which this test needs. I explicitly set the
  debugger tuning parameter to get the attribute always.
- darwin targets did not like the "section .text.startup" fragment of
  the test. This is not actually needed for the test, so I remove it.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@329555 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,apple/swift-llvm,apple/swift-llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,apple/swift-llvm,llvm-mirror/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm