ARM: 7583/1: decompressor: Enable unaligned memory access for v6 and above

Modern GCC can generate code which makes use of the CPU's native
unaligned memory access capabilities.  This is useful for the C
decompressor implementations used for unpacking compressed kernels.

This patch disables alignment faults and enables the v6 unaligned
access model on CPUs which support these features (i.e., v6 and
later), allowing full unaligned access support for C code in the
decompressor.

The decompressor C code must not be built to assume that unaligned
access works if support for v5 or older platforms is included in
the kernel.

For correct code generation, C decompressor code must always use
the get_unaligned and put_unaligned accessors when dealing with
unaligned pointers, regardless of this patch.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Enable UNALIGNED_ACCESS for LZO algorithm to use
lulzactive: here should be 0.. by default
lib/int_sqrt.c: optimize square root algorithm

Based on:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/
commit/?id=30493cc9dddb68066dcc4878015660fdaa8e0965
squashed update to writeback
squashed update of kernel from 3.4.67 to 3.4.68
Rocket & Nicole