Bluetooth: Fix compiler warning when VS HCI is unset

Fixes:

subsys/bluetooth/host/hci_core.c: In function ‘set_static_addr’:
subsys/bluetooth/host/hci_core.c:4043:1: error: label ‘generate’ defined
but not used [-Werror=unused-label]
 generate:
 ^~~~~~~~

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>