mesa: Don't resurrect deleted ARB VAOs in glPopClientAttrib

mesa: Don't resurrect deleted ARB VAOs in glPopClientAttrib

When ARB VAOs are used, glPopClientAttrib does not resurrect a deleted
VAO or VBO.  This difference between the two spec is, unfortunately,
not very well spelled out in the specs.

Fixes oglc vao(advanced.pushPop.deleteVAO) and
vao(advanced.pushPop.deleteVBO) tests.

NOTE: This is a candidate for release branches.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
(cherry picked from commit 34c353ce463960afdf64fa2be1f155b8b7f6c70c)