PCI: xilinx: Fix typo in function name

There's a typo in commit e39758e in linux-next, which incorrectly
spells "msi_desc_to_pci_sysdata()" as "msi_desc_to_pci_sys_data()" and
causes build failure:

> ../drivers/pci/host/pcie-xilinx.c:235:3: error: implicit declaration
    of function 'msi_desc_to_pci_sys_data' [-Werror=implicit-function-declaration]

Fixes: e39758e "PCI: Use helper functions to access fields in struct msi_desc"
Signed-off-by: Jiang Liu <[email protected]>
Cc: [email protected]
Cc: Mark Brown <[email protected]>
Cc: Stephen Rothwell <[email protected]>
Cc: Bjorn Helgaas <[email protected]>
Cc: Michal Simek <[email protected]>
Cc: Sören Brinkmann <[email protected]>
Cc: Srikanth Thokala <[email protected]>
Cc: Rob Herring <[email protected]>
Cc: Yijing Wang <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

Author: Jiang Liu

drivers/pci/host/pcie-xilinx.c

@@ -232,7 +232,7 @@ static void xilinx_pcie_destroy_msi(unsigned int irq)
 
 	if (!test_bit(irq, msi_irq_in_use)) {
 		msi = irq_get_msi_desc(irq);
-		port = sys_to_pcie(msi_desc_to_pci_sys_data(msi));
+		port = sys_to_pcie(msi_desc_to_pci_sysdata(msi));
 		dev_err(port->dev, "Trying to free unused MSI#%d\n", irq);
 	} else {
 		clear_bit(irq, msi_irq_in_use);