targets/dri: Add __driDriverGetExtensions_i915 symbol

Identical to previous commits - will bring us a step closer
to megadrivers.

Cc: Stephane Marchesin <stephane.marchesin@gmail.com>
Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Tested-by: Rob Clark <robclark@freedesktop.org>
Tested-by: Thomas Helland <thomashelland90 at gmail.com>
Acked-by: Tom Stellard <thomas.stellard@amd.com>

src/gallium/auxiliary/target-helpers/inline_drm_helper.h

@@ -51,6 +51,18 @@ static char* driver_name = NULL;
 /* XXX: We need to teardown the winsys if *screen_create() fails. */
 
 #if defined(GALLIUM_I915)
+#if defined(DRI_TARGET)
+#include "dri_screen.h"
+
+const __DRIextension **__driDriverGetExtensions_i915(void);
+
+PUBLIC const __DRIextension **__driDriverGetExtensions_i915(void)
+{
+   globalDriverAPI = &galliumdrm_driver_api;
+   return galliumdrm_driver_extensions;
+}
+#endif
+
 static struct pipe_screen *
 pipe_i915_create_screen(int fd)
 {

src/gallium/targets/dri/Makefile.am

@@ -13,6 +13,11 @@ AM_CPPFLAGS = \
 	-DGALLIUM_RBUG \
 	-DGALLIUM_TRACE
 
+if HAVE_GALLIUM_I915
+AM_CPPFLAGS += \
+	-DDRI_TARGET
+endif
+
 if HAVE_GALLIUM_NOUVEAU
 AM_CPPFLAGS += \
 	-DDRI_TARGET