UBI: fix debugging messages

commit 72f0d453d81d35087b1d3ad7c8285628c2be6e1d upstream.

Patch ab50ff684707031ed4bad2fdd313208ae392e5bb broke UBI debugging messages:
before that commit when UBI debugging was enabled, users saw few useful
debugging messages after attaching an MTD device. However, that patch turned
'dbg_msg()' into 'pr_debug()', so to enable the debugging messages users have
to enable them first via /sys/kernel/debug/dynamic_debug/control, which is
very impractical.

This commit makes 'dbg_msg()' to use 'printk()' instead of 'pr_debug()', just
as it was before the breakage.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/mtd/ubi/debug.h b/drivers/mtd/ubi/debug.h
index 3f1a09c..5f0e4c2 100644
--- a/drivers/mtd/ubi/debug.h
+++ b/drivers/mtd/ubi/debug.h
@@ -51,7 +51,10 @@
 	pr_debug("UBI DBG " type ": " fmt "\n", ##__VA_ARGS__)
 
 /* Just a debugging messages not related to any specific UBI subsystem */
-#define dbg_msg(fmt, ...) ubi_dbg_msg("msg", fmt, ##__VA_ARGS__)
+#define dbg_msg(fmt, ...)                                    \
+	printk(KERN_DEBUG "UBI DBG (pid %d): %s: " fmt "\n", \
+	       current->pid, __func__, ##__VA_ARGS__)
+
 /* General debugging messages */
 #define dbg_gen(fmt, ...) ubi_dbg_msg("gen", fmt, ##__VA_ARGS__)
 /* Messages from the eraseblock association sub-system */