video: s3c-fb: fix help message for FB_S3C_DEBUG_REGWRITE

The help message of config FB_S3C_DEBUG_REGWRITE is fixed,
because printk(KERN_DEBUG) was replaced with pr_debug().
Signed-off-by: NJingoo Han <jg1.han@samsung.com>

drivers/video/Kconfig

@@ -2045,7 +2045,7 @@ config FB_S3C_DEBUG_REGWRITE
        bool "Debug register writes"
        depends on FB_S3C
        ---help---
-         Show all register writes via printk(KERN_DEBUG)
+         Show all register writes via pr_debug()
 
 config FB_S3C2410
 	tristate "S3C2410 LCD framebuffer support"