Bluetooth: hci_qca: Rename STATE_<flags> to QCA_<flags>
Rename STATE_IN_BAND_SLEEP_ENABLED to QCA_IBS_ENABLED. The constant
represents a flag (multiple flags can be set at once), not a unique
state of the controller or driver.
Also make the flag an enum value instead of a pre-processor constant
(more flags will be added to the enum group by another patch).