glx: Add the extension string for GLX_ARB_framebuffer_sRGB

From the GLX perspective, the ARB and EXT extensions are identical.  Use
a single bit for both.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Cc: Maciej Wieczorek <maciej.t.wieczorek@intel.com>

src/glx/glxextensions.c

@@ -74,6 +74,7 @@ static const struct extension_info known_glx_extensions[] = {
    { GLX(ARB_create_context),          VER(0,0), Y, N, N, N },
    { GLX(ARB_create_context_profile),  VER(0,0), Y, N, N, N },
    { GLX(ARB_create_context_robustness), VER(0,0), Y, N, N, N },
+   { GLX(ARB_framebuffer_sRGB),        VER(0,0), Y, Y, N, N },
    { GLX(ARB_get_proc_address),        VER(1,4), Y, N, Y, N },
    { GLX(ARB_multisample),             VER(1,4), Y, Y, N, N },
    { GLX(ATI_pixel_format_float),      VER(0,0), N, N, N, N },

src/glx/glxextensions.h

@@ -65,6 +65,11 @@ enum
    INTEL_swap_event_bit,
 };
 
+/* From the GLX perspective, the ARB and EXT extensions are identical.  Use a
+ * single bit for both.
+ */
+#define ARB_framebuffer_sRGB_bit EXT_framebuffer_sRGB_bit
+
 enum
 {
    GL_ARB_depth_texture_bit = 0,