Fix Windows bot failure in Transforms/FunctionImport/funcimport.ll
Fix Windows bot failure in Transforms/FunctionImport/funcimport.ll

Make sure we split ":" from the end of the global function id (which
is <path>:<function> for local functions) instead of the beginning to
avoid splitting at the wrong place for Windows file paths that contain
a ":".

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@260469 91177308-0d34-0410-b5e6-96231b3b80d8

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