drm/i915: Don't use uninitialized 'ret'

Accidentally removed the 'ret=0' initialization, and thus
we're potentially looking at some stack garbage here.

The whole 'ret = do_stuff; if (!ret) do_other_stuff;' pattern
confuses my brain so let's replace it with the standard
immediate return thing.
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Fixes: 28a30b45 ("drm/i915: Convert cdclk to global state")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200207152228.1054-1-ville.syrjala@linux.intel.comReviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

drivers/gpu/drm/i915/display/intel_display.c

@@ -12843,11 +12843,13 @@ static int intel_crtc_atomic_check(struct intel_atomic_state *state,
 	}
 
 	if (INTEL_GEN(dev_priv) >= 9) {
-		if (mode_changed || crtc_state->update_pipe)
+		if (mode_changed || crtc_state->update_pipe) {
 			ret = skl_update_scaler_crtc(crtc_state);
-		if (!ret)
-			ret = intel_atomic_setup_scalers(dev_priv, crtc,
-							 crtc_state);
+			if (ret)
+				return ret;
+		}
+
+		ret = intel_atomic_setup_scalers(dev_priv, crtc, crtc_state);
 		if (ret)
 			return ret;
 	}