gallium: fix build breakage in st_cb_viewport.c

diff --git a/src/mesa/state_tracker/st_cb_viewport.c b/src/mesa/state_tracker/st_cb_viewport.c
index 7b175288fcb3061772da6edfcf203241ad88461f..75b0a219ce3a557ce8f4df086e3ae38c2292cdb5 100644 (file)
--- a/src/mesa/state_tracker/st_cb_viewport.c
+++ b/src/mesa/state_tracker/st_cb_viewport.c
@@ -34,6 +34,8 @@
 #include "pipe/p_inlines.h"
 #include "pipe/p_state.h"
 #include "pipe/p_defines.h"
+#include "pipe/internal/p_winsys_screen.h"
+
 
 static void st_viewport(GLcontext * ctx, GLint x, GLint y,
                         GLsizei width, GLsizei height)