[PATCH] ARM SMP: Fix vector entry

The current vector entry system does not allow for SMP.  In
order to work around this, we need to eliminate our reliance
on the fixed save areas, which breaks the way we enable
alignment traps.  This patch changes the way we handle the
save areas such that we can have one per CPU.

Signed-off-by: Russell King <rmk@arm.linux.org.uk>