i915: correctly parse/set the context flags

With an earlier commit we've spit the flags parsing to a separate
function, but forgot to update all the dri modules to use it.

Noticed when we've enabled KHR_debug for every dri module - fdo#93048

Fixes: 38366c0c6e "dri_util: Don't assume __DRIcontext->driverPrivate
is a gl_context"
Cc: Mark Janes <mark.a.janes@intel.com>
Cc: "11.0 11.1" <mesa-stable@lists.freedesktop.org>
Cc: Kristian Høgsberg <krh@bitplanet.net>
Cc: Ian Romanick <ian.d.romanick@intel.com>
Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: Mark Janes <mark.a.janes@intel.com>
Tested-by: Mark Janes <mark.a.janes@intel.com>

(cherry picked from commit 72fda2b710)

src/mesa/drivers/dri/i915/intel_context.c

@@ -426,6 +426,8 @@ intelInitContext(struct intel_context *intel,
       return false;
    }
 
+   driContextSetFlags(&intel->ctx, flags);
+
    driContextPriv->driverPrivate = intel;
    intel->driContext = driContextPriv;