Built-ins (e.g. gl_VertexID or gl_InstanceID) were settings dirty bits
in the driver's ActiveAttribLocationsMask which would later cause
the Vulkan back-end to issue bind commands on these built-in attributes
that don't have / need anything bound.

Test:
  angle_deqp_khr_gles31_tests --use-angle=swiftshader --gtest_filter=dEQP.KHR_GLES31/core_shader_storage_buffer_object_advancedswitchBuffersvs

Bug: angleproject:4107
Change-Id: Id1f1c6699d512d0726b22d9bb0c16abad179950d
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1972200Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Courtney Goeltzenleuchter <courtneygo@google.com>
Commit-Queue: Courtney Goeltzenleuchter <courtneygo@google.com>