drivers/dri: explicitly set __DRI2flushExtension members

Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>y
diff --git a/src/mesa/drivers/dri/nouveau/nouveau_screen.c b/src/mesa/drivers/dri/nouveau/nouveau_screen.c
index a381064..9929056 100644
--- a/src/mesa/drivers/dri/nouveau/nouveau_screen.c
+++ b/src/mesa/drivers/dri/nouveau/nouveau_screen.c
@@ -227,9 +227,10 @@
 }
 
 static const struct __DRI2flushExtensionRec nouveau_flush_extension = {
-    { __DRI2_FLUSH, 3 },
-    nouveau_drawable_flush,
-    dri2InvalidateDrawable,
+   .base = { __DRI2_FLUSH, 3 },
+
+   .flush               = nouveau_drawable_flush,
+   .invalidate          = dri2InvalidateDrawable,
 };
 
 static const struct __DRItexBufferExtensionRec nouveau_texbuffer_extension = {
diff --git a/src/mesa/drivers/dri/radeon/radeon_screen.c b/src/mesa/drivers/dri/radeon/radeon_screen.c
index 57e866e..90251db 100644
--- a/src/mesa/drivers/dri/radeon/radeon_screen.c
+++ b/src/mesa/drivers/dri/radeon/radeon_screen.c
@@ -192,9 +192,10 @@
 }
 
 static const struct __DRI2flushExtensionRec radeonFlushExtension = {
-    { __DRI2_FLUSH, 3 },
-    radeonDRI2Flush,
-    dri2InvalidateDrawable,
+   .base = { __DRI2_FLUSH, 3 },
+
+   .flush               = radeonDRI2Flush,
+   .invalidate          = dri2InvalidateDrawable,
 };
 
 static __DRIimage *