Perf: rewrite of ecp_double_jac
Perf: rewrite of ecp_double_jac

- Improve optimization for special case A == -3.
- Add optimization for special case A == 0.
- Use alternative base formula, saving several additions.
- Reduce temp variables to 4 (from 6).

Mbed-TLS/mbedtls,Mbed-TLS/mbedtls,ARMmbed/mbedtls,NXPmicro/mbedtls,NXPmicro/mbedtls,Mbed-TLS/mbedtls,ARMmbed/mbedtls,ARMmbed/mbedtls,NXPmicro/mbedtls,NXPmicro/mbedtls,ARMmbed/mbedtls,Mbed-TLS/mbedtls