ENGR00269945: reset: register gpio-reset driver in arch_initcall

ENGR00269945: reset: register gpio-reset driver in arch_initcall

It's a little bit late to register gpio-reset driver at module_init
time, because gpio-reset provides reset control via gpio for other
devices which are mostly probed at module_init time too.  And it
becomes even worse, when the gpio comes from IO expander on I2C bus,
e.g. pca953x.  In that case, gpio-reset needs to be ready before I2C
bus driver which is generally ready at subsys_initcall time.  Let's
register gpio-reset driver in arch_initcall() to have it ready early
enough.

The defer probe mechanism is not used here, because a reset controller
driver should be reasonably registered early than other devices.  More
importantly, defer probe doe not help in some nasty cases, e.g. the
gpio-pca953x device itself needs a reset from gpio-reset driver start
working.

Signed-off-by: Shawn Guo <shawn.guo@freescale.com>