Bluetooth: host: Update id.c to support id rst/del for CONFIG_BT_SMP=n

Currently calls to these two functions fail unnecessarily when
CONFIG_BT_SMP is disabled. This fix allows identity resets
without having the BT_SMP stack enabled. The primary use case
is enabling random mac address rotation for privacy in memory
constrained SOCs. Fixes #73313

Signed-off-by: Patrick Patel <ppatel@micro-design.com>