GL: Skip buffer validation for transform feedback buffers.
GL: Skip buffer validation for transform feedback buffers.

Transform feedback buffer state is managed by TransformFeedbackGL, the
state tracked in StateManagerGL is not correct.

BUG=angleproject:3900

Change-Id: I73f7b9b1c8d3b4087e25eb4cf3844faf210793a0
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1848392
Reviewed-by: Jonah Ryan-Davis <682bdb9e7d8ba359ef169b8db374e7a99d394a46@google.com>
Commit-Queue: Geoff Lang <b6fc25fe0362055230985c05cbfa8adb741ccc0f@chromium.org>

ppy/angle,ppy/angle,ppy/angle,ppy/angle