drm/i915: Allow relocation deltas outside of target bo

Userspace has a legitimate requirement to use a delta that points to
outside of the target bo, and so we need to enable this. (As this is an
abi break, albeit a relaxation of the current restrictions, mark the change
with a new flag.)

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

include/drm/i915_drm.h

@@ -290,6 +290,7 @@ typedef struct drm_i915_irq_wait {
 #define I915_PARAM_HAS_RELAXED_FENCING	 12
 #define I915_PARAM_HAS_COHERENT_RINGS	 13
 #define I915_PARAM_HAS_EXEC_CONSTANTS	 14
+#define I915_PARAM_HAS_RELAXED_DELTA	 15
 
 typedef struct drm_i915_getparam {
 	int param;