UBI: make debugging messages dynamic

This patch adds a possibility to dynamically select UBI debugging
messages, instead of selecting them compile-time from the configuration
menu. This is much more flexible, and consistent with UBIFS, and this
also simplifies UBI Kconfig menu and the code.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

drivers/mtd/ubi/debug.c

@@ -27,6 +27,14 @@
 #ifdef CONFIG_MTD_UBI_DEBUG
 
 #include "ubi.h"
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+
+unsigned int ubi_msg_flags;
+
+module_param_named(debug_msgs, ubi_msg_flags, uint, S_IRUGO | S_IWUSR);
+
+MODULE_PARM_DESC(debug_msgs, "Debug message type flags");
 
 /**
  * ubi_dbg_dump_ec_hdr - dump an erase counter header.