video: fbdev: s1d13xxxfb: Fix kernel-doc and set but not used warnings

Fix following W=1 warnings:
- Fix set but not used variables that were used only for logging.
Fixed by introducing no_printk() to trick compiler to think variables
are used
- Fix kernel-doc warning by deleting an empty comment line

v3:
- Fix grammar in commit message (Thomas)
v2:
- Subject updated (Lee)

Signed-off-by: Sam Ravnborg <[e-mail]>
Reviewed-by: Thomas Zimmermann <[e-mail]>
Cc: Kristoffer Ericson <[e-mail]>
Cc: Lee Jones <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/video/fbdev/s1d13xxxfb.c

···
 #if 0
 #define dbg(fmt, args...) do { printk(KERN_INFO fmt, ## args); } while(0)
 #else
-#define dbg(fmt, args...) do { } while (0)
+#define dbg(fmt, args...) do { no_printk(KERN_INFO fmt, ## args); } while (0)
 #endif
 
 /*
···
 }
 
 /**
- *
  *	s1d13xxxfb_bitblt_solidfill - accelerated solidfill function
  *	@info : framebuffer structure
  *	@rect : fb_fillrect structure