include/configs: Remove rootwait=1 to all the affected boards

rootwait=1 is not a valid kernel boot parameters. According
to the documenation is only rootwait

rootwait	[KNL]	Wait (indefinitely) for root device to show up.
			Useful for devices that are detected asynchronously
			(e.g. USB and MMC devices).

Fix:
Unknown kernel command line parameters "rootwait=1", will be passed to user space.

Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
Reviewed-by: Heiko Schocher <hs@denx.de>