Revert "ARM: 7593/1: nommu: do not enable DCACHE_WORD_ACCESS when !CONFIG_MMU"

This reverts commit 5d3648ca55ab70ee2a22ebf03219f1afa0560d49.
Revert "ARM: dcache: select DCACHE_WORD_ACCESS for little-endian ARMv6+ CPUs"

This reverts commit 76085161c60277584af6365192a0f82808e70095.
Revert "ARM: use generic strnlen_user and strncpy_from_user functions"

This reverts commit 2cdd3fb9813e7e21a33979fcad9a83e939892a93.