Add $genHType versions of frexp and ldexp.

Change-Id: I2c958b7aca972b7eec07e10d6c8af95fa53e761a
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/342117
Auto-Submit: John Stiles <johnstiles@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
6 files changed