sm: generate random number to display for SC with PK_RESP_INPUT generation mode

sm: fix ec key generation and logging

sm: fix legacy pairing trigger user response as responder

sm: use correct ec test key, reduce memory to 1500 bytes

sm: increase buffer for ec key generation

sm: add sm_use_fixed_ec_keypair, ENABLE_FIXED_LE_EC_KEY skips EC key generation saving 4400 bytes

sm: use custom memory allocator for mbedtls if not HAVE_MALLOC

sm: split mbedtls keypair into group. point, and value

sm: cache local ec key

sm: use mbedtls's memory allocator with 5k buffer if HAVE_MALLOC is not defined

sm: track calloc/free in mbedtls

sm: call mbedtls_x_free functions

sm: use LK from LE Device DB for SC in initiator role

sm: release setup context after sending LTK negative reply

sm: don't send encryption info for SC

sm: don't generate rand and LTK in SC

sm: use LTK from LE Device DB for SC in responder role

sm: fix transition to calculate local confirm in responder role

sm: wait for passkey entry if neccessarry

sm: use LE Random for local nonce before confirmation calculation

sm: use LE Random for initiator/jw_nk

sm: fix local nonce generation

sm: use fresh nonce for each passkey round

sm: fix sc passkey entry in responder role

sm: use LE Random command to generate EC keypair