watchdog: convert drivers/watchdog/* to use module_platform_driver_probe

This makes the code a bit smaller by getting rid of
some boilerplate code.

Signed-off-by: Fabio Porcedda <fabio.porcedda@gmail.com>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --cc drivers/watchdog/at32ap700x_wdt.c
Simple merge

diff --cc drivers/watchdog/at91sam9_wdt.c
Simple merge

diff --cc drivers/watchdog/coh901327_wdt.c
Simple merge

diff --cc drivers/watchdog/imx2_wdt.c
Simple merge

diff --cc drivers/watchdog/txx9wdt.c
Simple merge