[WATCHDOG] sizeof cleanup

Use sizeof(*) instead of sizeof * (See Codingstyle documentation).

Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

diff --cc drivers/watchdog/iop_wdt.c
Simple merge

diff --cc drivers/watchdog/rm9k_wdt.c
Simple merge

diff --cc drivers/watchdog/sc1200wdt.c
Simple merge