drm/i915: SAGV is not SKL-only, so rename a few things

The plan is to introduce intel_has_sagv() and then use it to discover
which platforms actually support it.

I thought about keeping the functions with their current skl names,
but found two problems: (i) skl_has_sagv() would become a very
confusing name, and (ii) intel_atomic_commit_tail() doesn't seem to be
calling any functions whose name start with a platform name, so the
"intel_" naming scheme seems make more sense than the "firstplatorm_"
naming scheme here.

Cc: stable@vger.kernel.org
Reviewed-by: Lyude <cpaul@redhat.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-2-git-send-email-paulo.r.zanoni@intel.com
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index c0f0f11..23bc43d 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1988,11 +1988,11 @@
 	struct vlv_s0ix_state vlv_s0ix_state;
 
 	enum {
-		I915_SKL_SAGV_UNKNOWN = 0,
-		I915_SKL_SAGV_DISABLED,
-		I915_SKL_SAGV_ENABLED,
-		I915_SKL_SAGV_NOT_CONTROLLED
-	} skl_sagv_status;
+		I915_SAGV_UNKNOWN = 0,
+		I915_SAGV_DISABLED,
+		I915_SAGV_ENABLED,
+		I915_SAGV_NOT_CONTROLLED
+	} sagv_status;
 
 	struct {
 		/*