Bluetooth: host: Remove cancel sync from database hash commit

Fix deadlock when db_hash_commit has to wait for the delayed work to
finish. This creates a deadlock if the delayed work for database hash
calculation needs to store the hash since the settings API is locked
when calling the commit callback.
Remove call to k_work_cancel_delayable_sync from db_hash_commit in order
to avoid the deadlock. Instead move comparing of the stored hash to the
delayed work and reschedule the work with no wait.

Signed-off-by: Joakim Andersson <joakim.andersson@nordicsemi.no>