iwlwifi: pcie: enable interrupts explicitly on resume

When entering suspend the driver calls iwl_disable_interrupts() and
then iwl_pcie_disable_ict().
On resume the driver calls only iwl_pcie_reset_ict() without calling
explicitly to iwl_enable_interrupts().
This mostly works since iwl_pcie_reset_ict is calling to
iwl_enable_interrupts, but it doesn't work when there is no ict_table
in MSIx mode.
The result is that driver tries to resume but fails since it doesn't
get the RX interrupt from FW indicating that d0i3 exit was completed.
Fix it by adding an explicit call to enable interrupts.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>