drm/i915/uc: Drop unnecessary forward declaration

We don't need it here.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171004153327.32608-3-michal.wajdeczko@intel.com

drivers/gpu/drm/i915/intel_uc.h

@@ -30,8 +30,6 @@
 #include "intel_guc_ct.h"
 #include "i915_vma.h"
 
-struct drm_i915_gem_request;
-
 /*
  * This structure primarily describes the GEM object shared with the GuC.
  * The specs sometimes refer to this object as a "GuC context", but we use