Makefile flag tweaks

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Added optimized ARM RWSEM algorithm.

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
evita: enable optimized ARM RWSEM algorithm
Makefile: set ARCH, CROSS_COMPILE for my custom toolchain
Revert "Added optimized ARM RWSEM algorithm."

This reverts commit cbc80d0e35fbb6d817331384b4895d87c5f285a6.
Revert "evita: enable optimized ARM RWSEM algorithm"

This reverts commit 17d9888d020f42108077e671cc78c9e12239db52.