iwlwifi: allow memory debug TLV to specify the memory type

Due to some new features and changes, the firmware file will now
specify what type of memory to dump, in upper 8 bits of the type
field of the TLV. Parse it (types we don't understand are errors)
and teach the code to dump periphery memory.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>