[ARM] nommu: add arch/arm/Kconfig-nommu to Kconfig files

Include Kconfig-nommu when MMU is not selected.

(This is part of a patch from Hyok.)

Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>