glx: add missing sRGB attribute check in fbconfigs_compatible()

This patch will allow driver to choose srgb capable FBconfig
if GLX_FRAMEBUFFER_SRGB_CAPABLE_ARB attribute is 1

Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Charmaine Lee <charmainel@vmware.com>
diff --git a/src/glx/glxcmds.c b/src/glx/glxcmds.c
index 53c9f9c..309d550 100644
--- a/src/glx/glxcmds.c
+++ b/src/glx/glxcmds.c
@@ -1014,6 +1014,7 @@
 
    MATCH_MASK(drawableType);
    MATCH_MASK(renderType);
+   MATCH_DONT_CARE(sRGBCapable);
 
    /* There is a bug in a few of the XFree86 DDX drivers.  They contain
     * visuals with a "transparent type" of 0 when they really mean GLX_NONE.