common: Drop LOGLEVEL to 4

While this came in with a default value of 6 I am lowering this to 4.
The MTD/UBI code has a large number of error messages that we include
now.  In addition, "normally" warning messages are not included so this
feels like a more natural level to have.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/common/Kconfig b/common/Kconfig
index f53ee9d..3c99650 100644
--- a/common/Kconfig
+++ b/common/Kconfig
@@ -243,7 +243,7 @@
 
 config LOGLEVEL
 	int "loglevel"
-	default 6
+	default 4
 	range 0 8
 	help
 	  All Messages with a loglevel smaller than the console loglevel will