matrix: Unroll the is_2d() operator
matrix: Unroll the is_2d() operator

The is_2d() implementation inside graphene_simd4x4f_t is susceptible to
floating point rounding errors. We can make the public wrapper API inside
graphene_matrix_t a bit more forgiving, by using the private fuzzy
comparison macro.

ebassi/graphene,ebassi/graphene,criptych/graphene,criptych/graphene,criptych/graphene,criptych/graphene