wifi: iwlwifi: remove dead code in iwl_dump_ini_imr_get_size()

Remove the check for the IMR debug data size which
leads to dead code.

Signed-off-by: Mukesh Sisodiya <mukesh.sisodiya@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230531194630.58eec8d40729.Ifb7d64706eed45726db804f36e785283dff7adab@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>