staging: line6: drop unused CONFIG_LINE6_USB_DEBUG

The CONFIG_LINE6_USB_DEBUG option is no longer relevant since dyndbg
dev_dbg() is now used instead of a compile-time decision whether to
enable debug messages or not.
Signed-off-by: NStefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/line6/Kconfig

@@ -23,14 +23,6 @@ menuconfig LINE6_USB
 
 if LINE6_USB
 
-config LINE6_USB_DEBUG
-	bool "print debug messages"
-	default n
-	help
-	  Say Y here to write debug messages to the syslog.
-
-	  If unsure, say N.
-
 config LINE6_USB_DUMP_CTRL
 	bool "dump control messages"
 	default n