drm/cirrus: Add some local 'fb' variables

Add a local 'fb' variable to a few places to get rid of the
'crtc->primary->fb' stuff. Looks neater and helps me with my poor
coccinelle skills later.

Cc: Dave Airlie <airlied@redhat.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1479498793-31021-8-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/cirrus/cirrus_mode.c

@@ -185,6 +185,7 @@ static int cirrus_crtc_mode_set(struct drm_crtc *crtc,
 {
 	struct drm_device *dev = crtc->dev;
 	struct cirrus_device *cdev = dev->dev_private;
+	const struct drm_framebuffer *fb = crtc->primary->fb;
 	int hsyncstart, hsyncend, htotal, hdispend;
 	int vtotal, vdispend;
 	int tmp;
@@ -257,7 +258,7 @@ static int cirrus_crtc_mode_set(struct drm_crtc *crtc,
 	sr07 = RREG8(SEQ_DATA);
 	sr07 &= 0xe0;
 	hdr = 0;
-	switch (crtc->primary->fb->bits_per_pixel) {
+	switch (fb->bits_per_pixel) {
 	case 8:
 		sr07 |= 0x11;
 		break;
@@ -280,13 +281,13 @@ static int cirrus_crtc_mode_set(struct drm_crtc *crtc,
 	WREG_SEQ(0x7, sr07);
 
 	/* Program the pitch */
-	tmp = crtc->primary->fb->pitches[0] / 8;
+	tmp = fb->pitches[0] / 8;
 	WREG_CRT(VGA_CRTC_OFFSET, tmp);
 
 	/* Enable extended blanking and pitch bits, and enable full memory */
 	tmp = 0x22;
-	tmp |= (crtc->primary->fb->pitches[0] >> 7) & 0x10;
-	tmp |= (crtc->primary->fb->pitches[0] >> 6) & 0x40;
+	tmp |= (fb->pitches[0] >> 7) & 0x10;
+	tmp |= (fb->pitches[0] >> 6) & 0x40;
 	WREG_CRT(0x1b, tmp);
 
 	/* Enable high-colour modes */