arm: select HAVE_EFFICIENT_UNALIGNED_ACCESS for CPUv6+ && MMU
Modern ARM CPUs can perform efficient unaligned memory accesses in
hardware and this feature is relied up on by code such as the dcache
word-at-a-time name hashing.

Commit: https://github.com/androidarmv6/android_kernel_samsung_bcm21553-common/commit/14a6db6a3aa9a6515105a7c6afca56fffd21854d