[PATCH][next] fbdev: sh7760fb: Fix -Wimplicit-fallthrough warnings

["Gustavo A. R. Silva" <gustavoars@xxxxxxxxxx>]

Fix the following fallthrough warnings seen after building sh
architecture with sh7763rdp_defconfig configuration:

drivers/video/fbdev/sh7760fb.c: In function 'sh7760fb_get_color_info':
drivers/video/fbdev/sh7760fb.c:138:23: warning: this statement may fall through [-Wimplicit-fallthrough=]
  138 |                 lgray = 1;
      |                 ~~~~~~^~~
drivers/video/fbdev/sh7760fb.c:139:9: note: here
  139 |         case LDDFR_4BPP:
      |         ^~~~
drivers/video/fbdev/sh7760fb.c:143:23: warning: this statement may fall through [-Wimplicit-fallthrough=]
  143 |                 lgray = 1;
      |                 ~~~~~~^~~
drivers/video/fbdev/sh7760fb.c:144:9: note: here
  144 |         case LDDFR_8BPP:
      |         ^~~~

Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
---
 drivers/video/fbdev/sh7760fb.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/video/fbdev/sh7760fb.c b/drivers/video/fbdev/sh7760fb.c
index 768011bdb430..98c5227098a8 100644
--- a/drivers/video/fbdev/sh7760fb.c
+++ b/drivers/video/fbdev/sh7760fb.c
@@ -136,11 +136,13 @@ static int sh7760fb_get_color_info(struct device *dev,
 		break;
 	case LDDFR_4BPP_MONO:
 		lgray = 1;
+		fallthrough;
 	case LDDFR_4BPP:
 		lbpp = 4;
 		break;
 	case LDDFR_6BPP_MONO:
 		lgray = 1;
+		fallthrough;
 	case LDDFR_8BPP:
 		lbpp = 8;
 		break;
-- 
2.34.1