mesa: add ARB_texture_barrier support

This extension is identical to NV_texture_barrier. Alias
glTextureBarrier to the existing glTextureBarrierNV and use the existing
NV_texture_barrier extension bit.

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
diff --git a/docs/relnotes/10.3.html b/docs/relnotes/10.3.html
index 556eaae..66745b8 100644
--- a/docs/relnotes/10.3.html
+++ b/docs/relnotes/10.3.html
@@ -55,6 +55,7 @@
 <li>GL_ARB_sample_shading on radeonsi</li>
 <li>GL_ARB_seamless_cubemap_per_texture on i965, llvmpipe, nvc0, r600, radeonsi, softpipe</li>
 <li>GL_ARB_stencil_texturing on nv50, nvc0, r600, and radeonsi</li>
+<li>GL_ARB_texture_barrier on nv50, nvc0, r300, r600, radeonsi</li>
 <li>GL_ARB_texture_compression_bptc on i965/gen7+, nvc0, r600/evergreen+, radeonsi</li>
 <li>GL_ARB_texture_cube_map_array on radeonsi</li>
 <li>GL_ARB_texture_gather on r600, radeonsi</li>