Algorithm encoding: move two bits from derivation to agreement
Algorithm encoding: move two bits from derivation to agreement

This gives a little more room to encode key agreement algorithms,
while keeping enough space for key derivation algorithms.

This doesn't affect any of the already-defined algorithms.

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