iwlwifi: pcie: move msix conf functions above other functions

msix configuration functions should be called by other functions.
For example by pcie_d3_resume, move it above to enable it.

Signed-off-by: Haim Dreyfuss <haim.dreyfuss@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>