Revert "ARM: 7835/2: fix modular build of xor_blocks() with NEON enabled"

This reverts commit 2bdb094ca1b95f57305b50ac9079dbc130806799.
Revert "ARM: crypto: add NEON accelerated XOR implementation"

This reverts commit 68785e5de499c03573f4b392ff266ec412723a2e.