Build - Clang: substitute fpu neon-vfp[3|4] for fpu neon

Clang does not natively support the neon-vfp option
so we will substitute it for neon.
This allows neon-vfp to be set for gcc, and won't cause
clang to error out.

Clang will enable neon and a vfp automatically with supported
cpu's.
Do not set fpu to vfp[3|4] as this may remove neon

Change-Id: I3f5f047b1feeb6f966926c18691e0c003b07f9a3
Signed-off-by: STELIX <ssspinni@gmail.com>