wifi: iwlwifi: add iwl_trans_device_enabled() API

add iwl_trans_device_enabled() function to be called by the op modes
instead of directly checking the trans status bits. This
hides the trans internal implementation details.

Signed-off-by: Rotem Kerem <rotem.kerem@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20250710212632.bb957ba9e130.I6ab825caf41308fb0f7aa1c266f50457fd0c496e@changeid