ARM: fix user unalignment prefetch abort

Branching to an address in ARM state which is not
word aligned, where this is defined to be UNPREDICTABLE,
can cause one of the following two behaviours: 1. The
unaligned location is forced to be aligned. 2. Using
the unaligned address generates a Prefetch Abort on the
first instruction using the unaligned PC value.

To be consistant for the user space binaries, the
unaligned location is forced aligned with this config.

Change-Id: I30eb9e5ffd886b746a46ff0ba1b0279e578fc201
Signed-off-by: Maria Yu <aiquny@codeaurora.org>