[RegisterBankInfo] Change the semantic of recordRegBankForType.
[RegisterBankInfo] Change the semantic of recordRegBankForType.

Now, recordRegBankForType records only the first register bank that
covers a type instead of the last. This behavior can, nevertheless, be
override with the additional Force parameter to force the update.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@265741 91177308-0d34-0410-b5e6-96231b3b80d8

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