[MIPS] Initialization of Alchemy boards

An earlier update changed some calls from simple_strotl to strict_strtol but
did not account for the differences in the syntax between the calls.
simple_strotl returns the integer; strict_strtol returns an error code and
takes a pointer to the result.  As it was, NULL was being passed in place of
the result, which led to failures during kernel initialization when using
YAMON.

Signed-off-by: Kevin Hickey <khickey@rmicorp.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>