[WATCHDOG] fix mtx1_wdt compilation failure

Using spin_lock_irqsave with a local variable called flags without
declaring is a bad idea, fix this by declaring it.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

1 file changed