ARM: 8028/1: move __fixup_smp out of init section

With large kernel builds such as allyesconfig exceeding maximum relative
branch offsets, the init section will be too far away to branch to
directly. This causes veneers to be added by the linker, but veneers
don't work before the MMU is enabled. Fix this by moving __fixup_smp to
the .head.text section as it is not very big.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>