divmod.c: simple test of integer division/modulus

Signed-off-by: Steven Noonan <steven@uplinklabs.net>
vector functions: implement float32x4 variants

Signed-off-by: Steven Noonan <steven@uplinklabs.net>
rsqrt.c: adding simple reciprocal square root functions

Signed-off-by: Steven Noonan <steven@uplinklabs.net>