fbdev: imxfb: use __func__ for function name

Resolve the following warning reported by checkpatch:

WARNING: Prefer using '"%s...", __func__' to using 'imxfb_blank', this function's name, in a string
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Helge Deller <deller@gmx.de>

drivers/video/fbdev/imxfb.c

@@ -576,7 +576,7 @@ static int imxfb_blank(int blank, struct fb_info *info)
 {
 	struct imxfb_info *fbi = info->par;
 
-	pr_debug("imxfb_blank: blank=%d\n", blank);
+	pr_debug("%s: blank=%d\n", __func__, blank);
 
 	switch (blank) {
 	case FB_BLANK_POWERDOWN: