ntb_hw_amd: Remove redundant pci_clear_master

Remove pci_clear_master to simplify the code,
the bus-mastering is also cleared in do_pci_disable_device,
like this:
./drivers/pci/pci.c:2197
static void do_pci_disable_device(struct pci_dev *dev)
{
u16 pci_command;

pci_read_config_word(dev, PCI_COMMAND, &pci_command);
if (pci_command & PCI_COMMAND_MASTER) {
pci_command &= ~PCI_COMMAND_MASTER;
pci_write_config_word(dev, PCI_COMMAND, pci_command);
}

pcibios_disable_device(dev);
}.
And dev->is_busmaster is set to 0 in pci_disable_device.

Signed-off-by: Cai Huoqing <[e-mail]>
Signed-off-by: Jon Mason <[e-mail]>

drivers/ntb/hw/amd/ntb_hw_amd.c

···
 	return 0;
 
 err_dma_mask:
-	pci_clear_master(pdev);
 	pci_release_regions(pdev);
 err_pci_regions:
 	pci_disable_device(pdev);
···
 
 	pci_iounmap(pdev, ndev->self_mmio);
 
-	pci_clear_master(pdev);
 	pci_release_regions(pdev);
 	pci_disable_device(pdev);
 	pci_set_drvdata(pdev, NULL);