[SCSI] qla2xxx: Use pcie_is_pcie() to simplify code

Use pci_is_pcie() instead of pci_find_capability() to simplify code.

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Chad Dupuis <chad.dupuis@qlogic.com>
Cc: Andrew Vasquez <andrew.vasquez@qlogic.com>
Cc: linux-driver@qlogic.com
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>