dbx500-prcmu: use cpu_is() instead of machine_is()

cpu_is_u5500() is what is really meant here, since machine_is_u5500() will
return false on U5500-based boards which use a different mach type.

Change-Id: I50c4512d7a070ee8203a307a9b87da492763aff6
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/32524
Reviewed-by: Jonas ABERG <jonas.aberg@stericsson.com>
1 file changed