[MIPS GlobalISel] Remove switch statement (fix r349346 for MSVC)
[MIPS GlobalISel] Remove switch statement (fix r349346 for MSVC)

Temporarily remove switch statement without any case labels 
in function legalizeCustom in order to fix r349346 for MSVC.



git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@349356 91177308-0d34-0410-b5e6-96231b3b80d8

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