mesa: Rename "struct gl_array_object" to gl_vertex_array_object.

mesa: Rename "struct gl_array_object" to gl_vertex_array_object.

I considered replacing it with "gl_vao", but spelling it out seemed to
fit better with Mesa's traditional style.  Mesa doesn't shy away from
long type names - consider gl_transform_feedback_object,
gl_fragment_program_state, gl_uniform_buffer_binding, and so on.

Completely generated by:
$ find . -type f -print0 | xargs -0 sed -i \
  's/gl_array_object/gl_vertex_array_object/g'

v2: Rerun command to resolve conflicts with Ian's meta patches.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Brian Paul <brianp@vmware.com>