ARM: set SCTRL[A] only when architecture does not support unaligned access
Recent gcc generates code with unaligned access when architecture
supports it. Setting A bit unconditionally causes data-aborts on such
code rendering barebox unusable.
Signed-off-by: Enrico Scholz <enrico.scholz@sigma-chemnitz.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>