Revert "i965: Create ARGB2101010 DRI configs"

Exposing 10-bit color configs confuses too many applications that try to
use the chooser to pick an 8 bit config.  The chooser consider an fbconfig
with more bits a better match and will thus give a 10 bit config when an
application asks for a config with GLX_RED_SIZE 1 or 8.

One key example is glxinfo, which does this, and then doesn't specify that
it needs a config where GLX_DRAWABLE_TYPE has the GLX_WINDOW_BIT set.
This way it ends up with a 10 bit config that it can't use to create a
GLX window and fails to log extensions.

This reverts commit f354bcc177.

https://bugs.freedesktop.org/show_bug.cgi?id=70557

src/mesa/drivers/dri/i965/intel_screen.c

@@ -921,8 +921,6 @@ intelCreateBuffer(__DRIscreen * driScrnPriv,
 
    if (mesaVis->redBits == 5)
       rgbFormat = MESA_FORMAT_RGB565;
-   else if (mesaVis->redBits == 10)
-      rgbFormat = MESA_FORMAT_ARGB2101010;
    else if (mesaVis->sRGBCapable)
       rgbFormat = MESA_FORMAT_SARGB8;
    else if (mesaVis->alphaBits == 0)
@@ -1052,8 +1050,7 @@ intel_screen_make_configs(__DRIscreen *dri_screen)
 {
    static const gl_format formats[] = {
       MESA_FORMAT_RGB565,
-      MESA_FORMAT_ARGB8888,
-      MESA_FORMAT_ARGB2101010
+      MESA_FORMAT_ARGB8888
    };
 
    /* GLX_SWAP_COPY_OML is not supported due to page flipping. */