Refactor HAL to GL format conversions. Bug 25390254 Change-Id: I434e6d319335be00204eff88f09c98b2dd4f2acc Reviewed-on: https://swiftshader-review.googlesource.com/4188 Reviewed-by: Alexis Hétu <sugoi@google.com> Tested-by: Nicolas Capens <capn@google.com> Reviewed-by: Nicolas Capens <capn@google.com>