fbdev: uninline lock_fb_info()

Before:

   text    data     bss     dec     hex filename
   3648    2910      32    6590    19be drivers/video/backlight/backlight.o
   3226    2812      32    6070    17b6 drivers/video/backlight/lcd.o
  30990   16688    8480   56158    db5e drivers/video/console/fbcon.o
  15488    8400      24   23912    5d68 drivers/video/fbmem.o

After:

   text    data     bss     dec     hex filename
   3537    2870      32    6439    1927 drivers/video/backlight/backlight.o
   3131    2772      32    5935    172f drivers/video/backlight/lcd.o
  30876   16648    8480   56004    dac4 drivers/video/console/fbcon.o
  15506    8400      24   23930    5d7a drivers/video/fbmem.o

Cc: Andrea Righi <righi.andrea@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c
index b64f061..2ac32e6 100644
--- a/drivers/video/fbmem.c
+++ b/drivers/video/fbmem.c
@@ -46,6 +46,17 @@
 struct fb_info *registered_fb[FB_MAX] __read_mostly;
 int num_registered_fb __read_mostly;
 
+int lock_fb_info(struct fb_info *info)
+{
+	mutex_lock(&info->lock);
+	if (!info->fbops) {
+		mutex_unlock(&info->lock);
+		return 0;
+	}
+	return 1;
+}
+EXPORT_SYMBOL(lock_fb_info);
+
 /*
  * Helpers
  */