mvebe: Drop ARCH_MISC_INIT from alleycat 5

In this platform, arch_misc_init doesn't perform any real function. The
call to get_soc_type_rev has no lasting side effects.

Cc: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Tom Rini <trini@konsulko.com>