BitcodeWriter: Rename some functions for consistency, NFC
BitcodeWriter: Rename some functions for consistency, NFC

To match writeMetadataRecords, writeNamedMetadata and
writeMetadataStrings, change:

    WriteModuleMetadata        => writeModuleMetadata
    WriteFunctionLocalMetadata => writeFunctionMetadata
    Write##CLASS               => write##CLASS

The only major change is "FunctionLocal" => "Function".  The point is to
be less specific, in preparation for emitting normal metadata records
inside function metadata blocks (currently we only emit
`LocalAsMetadata` there).

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@264556 91177308-0d34-0410-b5e6-96231b3b80d8

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