wifi: iwlwifi: dbg: add support for DBGC4 on BZ family and above

Update the for loop that iterates over all the DBGCs to include DBGC4.
DBGC4 is only supported staring from the BZ family of devices, so check
the family before accepting it.

Signed-off-by: Rotem Saado <rotem.saado@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20221102165239.0b6050b41060.Id662c716c2e3c2c850740d1f71e2801e02aeddaf@changeid