iwlwifi: dbg_ini: maintain buffer allocations from trans instead of TLVs buffer

Maintain DRAM debug buffer status in trans instead of keeping it as
part of the TLVs buffer to avoid allocating extra space for it.
Needed for future changes.

Signed-off-by: Shahar S Matityahu <shahar.s.matityahu@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>