When The driver in D3 and FW crash happens, trans->system_pm_mode
is  not reset to IWL_PLAT_PM_MODE_DISABLED which causes the driver
not to send INIT conmmands and D3 resume fails.

This patch contains the fix for resetting trans->system_pm_mode to
IWL_PLAT_PM_MODE_DISABLED and D3 resume is successful.
Signed-off-by: Ravi Darsi <ravi.darsi@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20210210172142.ad170ad48409.Ifc6b10e8b3f235876af91d0e23e90b462d270eff@changeidSigned-off-by: Luca Coelho <luciano.coelho@intel.com>