drm/i915: s/__raw_i915_read32/I915_READ_FW/ in the SKL+ scanline read w/a

Replace __raw_i915_read32() with I915_READ_FW() in the workaround for
the SKL+ scanline counter hardware fail. The two are the same thing
but everyone else uses I915_READ_FW() so let's follow suit.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170309154434.29303-3-ville.syrjala@linux.intel.com
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

drivers/gpu/drm/i915/i915_irq.c

@@ -812,8 +812,7 @@ static int __intel_get_crtc_scanline(struct intel_crtc *crtc)
 
 		for (i = 0; i < 100; i++) {
 			udelay(1);
-			temp = __raw_i915_read32(dev_priv, PIPEDSL(pipe)) &
-				DSL_LINEMASK_GEN3;
+			temp = I915_READ_FW(PIPEDSL(pipe)) & DSL_LINEMASK_GEN3;
 			if (temp != position) {
 				position = temp;
 				break;