mesa: Remove ARB_texture_mirrored_repeat extension enable flag

All drivers remaining in Mesa support this extension.  This extension
is either required or optional features in desktop OpenGL, OpenGL ES
1.x, and OpenGL ES 2.x.

This extension was previously not supported on mach64, mga, and savage
(Savage3D and other pre-Savage4).

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
14 files changed