vnc: Remove the superfluous break

Remove the superfluous break, as there is a "return" before.

Signed-off-by: Liao Pingfang <liao.pingfang@zte.com.cn&gt;a>
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1594631086-36509-1-git-send-email-wang.yi59@zte.com.cn>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

ui/vnc-enc-tight.c

@@ -1125,7 +1125,6 @@ static int send_palette_rect(VncState *vs, int x, int y,
     }
     default:
         return -1; /* No palette for 8bits colors */
-        break;
     }
     bytes = w * h;
     vs->tight->tight.offset = bytes;