[ARM] 3229/1: Remove uneeded ARM apm dependency on PM_LEGACY

Patch from Richard Purdie

ARM doesn't use ACPI so ARM's apm implementation has no need to depend
on PM_LEGACY. This patch removes that dependency.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>