PCI: imx6: Use tabs for indentation

[ Upstream commit d88a7ef9 ]

This patch fixes the following checkpatch error:

  ERROR: code indent should use tabs where possible
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>