Make ec_GFp_simple_point_get_affine_coordinates() faster for Montgomery representations.
Make ec_GFp_simple_point_get_affine_coordinates() faster
for Montgomery representations.

Submitted by: Sheueling Chang, Bodo Moeller

openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl