This fixes most of the test for
dEQP 3.1 KHR-GLES31.core.vertex_attrib_binding.basic-input*

The bug fixes is that we were not correctly setting the vertex attribute
offset for vertex attribs that were converted into their own buffer.
We kept the attrib offset from the frontend as if the converted attribs
were in the original buffer, but converted vtx attrib buffers in the VK
backend are tightly packed from the start of the buffer so when converting
the actual offset should be 0.

Also, in order to avoid a VK validation error, this change includes a tmp
workaround to make sure transform feedback output buffer range is never 0,
but sets VK_WHOLE_SIZE in that case. A follow-on fix that focuses on
transform feedback fixes will address this validation error more fully.

Bug: angleproject:4145
Bug: angleproject:4236
Change-Id: I8c218954725945414a8f18beb4f964b90da7062a
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1980906
Commit-Queue: Tobin Ehlis <tobine@google.com>
Reviewed-by: Courtney Goeltzenleuchter <courtneygo@google.com>
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>