megaraid: Use pci_enable_msix_range() instead of pci_enable_msix()

As result of deprecation of MSI-X/MSI enablement functions
pci_enable_msix() and pci_enable_msi_block() all drivers
using these two interfaces need to be updated to use the
new pci_enable_msi_range()  or pci_enable_msi_exact()
and pci_enable_msix_range() or pci_enable_msix_exact()
interfaces.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Acked-by: Kashyap Desai <Kashyap.desai@avagotech.com>
Cc: Neela Syam Kolli <megaraidlinux@lsi.com>
Cc: linux-scsi@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Signed-off-by: Christoph Hellwig <hch@lst.de>