ACPI, APEI: Cleanup alignment-aware accesses

ACPI, APEI: Cleanup alignment-aware accesses

We do use memcpy to avoid access alignment issues between firmware and
OS. Now we can use a better and standard way to avoid this issue. While
at it, simplify some variable names to avoid the 80 cols limit and
use structure assignment instead of unnecessary memcpy. No functional
changes.

Because ERST record id cache is implemented in memory to increase the
access speed via caching ERST content we can refrain from using memcpy
there too and use regular assignment instead.

Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
Cc: Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/1387348249-20014-1-git-send-email-gong.chen@linux.intel.com
[ Boris: massage commit message a bit. ]
Signed-off-by: Borislav Petkov <bp@suse.de>