net/mlx5: Include linux/pci.h for pci_msix_can_alloc_dyn()

Add include directive to assure pci_msix_can_alloc_dyn() prototype.

Fixes: 3354822c ("net/mlx5: Use dynamic msix vectors allocation")
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202303291328.sNmTyyWF-lkp@intel.com/


Signed-off-by: Eli Cohen <elic@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>