mesa: add AllowGLSLCrossStageInterpolationMismatch workaround

This fixes issues seen with certain versions of Unreal Engine 4 editor
and games built with that using GLSL 4.30.

v2: add driinfo_gallium change (Emil Velikov)

Signed-off-by: Tapani Pälli <tapani.palli@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97852
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103801
Acked-by: Andres Gomez <agomez@igalia.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

src/util/drirc

@@ -160,6 +160,14 @@ TODO: document the other workarounds.
             <option name="glsl_correct_derivatives_after_discard" value="true"/>
         </application>
 
+        <application name="Unreal 4 Editor" executable="UE4Editor">
+            <option name="allow_glsl_cross_stage_interpolation_mismatch" value="true"/>
+        </application>
+
+        <application name="Observer" executable="TheObserver-Linux-Shipping">
+            <option name="allow_glsl_cross_stage_interpolation_mismatch" value="true"/>
+        </application>
+
         <!-- The GL thread whitelist is below, workarounds are above.
              Keep it that way. -->
 

src/util/xmlpool/t_options.h

@@ -135,6 +135,10 @@ DRI_CONF_OPT_BEGIN_B(glsl_correct_derivatives_after_discard, def) \
         DRI_CONF_DESC(en,gettext("Implicit and explicit derivatives after a discard behave as if the discard didn't happen")) \
 DRI_CONF_OPT_END
 
+#define DRI_CONF_ALLOW_GLSL_CROSS_STAGE_INTERPOLATION_MISMATCH(def) \
+DRI_CONF_OPT_BEGIN_B(allow_glsl_cross_stage_interpolation_mismatch, def) \
+        DRI_CONF_DESC(en,gettext("Allow interpolation qualifier mismatch across shader stages")) \
+DRI_CONF_OPT_END
 
 /**
  * \brief Image quality-related options