arm: tegra: pcie: WAR to avoid hang on PCIe device

Setting DFPCI_RSPPASSPW bit in AFI_CONFIGURATION
register to avoid instant hang on CPU read/write
while gpu transfers are in progress.

Bug 1034443

Change-Id: I40c99588753b8b2cb2d418b54c6ac73f7b8ddc13
Signed-off-by: Jay Agarwal <jagarwal@nvidia.com>
Reviewed-on: http://git-master/r/124037
Reviewed-by: Simone Willett <swillett@nvidia.com>
Tested-by: Simone Willett <swillett@nvidia.com>