CVE-2023-48795: client side mitigation

include/libssh/packet.h

include/libssh/session.h

src/curve25519.c

src/dh-gex.c

src/dh.c

src/ecdh.c

src/ecdh_crypto.c

src/ecdh_gcrypt.c

src/ecdh_mbedcrypto.c

src/kex.c

src/packet.c

src/packet_cb.c