Modify ocf_metadata_hash_func to return consecutive (modulo @hash_table_entries)
values for consecutive @core_line_num. This way it is trivial to sort all
core lines within a single request according to their hash value. This kind
of sorting will be required to assure that future hash bucket metadata locks
are always acquired in fixed order, eliminating the risk of dead locks.
This change is part of fine granularity metadata lock implementation.
Signed-off-by: Adam Rutkowski <adam.j.rutkowski@intel.com>
