PCI: designware: Fix indent code style

Fix indent code style and replace 'MSI interrupt controller' of comment
with 'MSI controller' to fix the following checkpatch issues:

  ERROR: code indent should use tabs where possible
  WARNING: please, no spaces at the start of a line
  WARNING: line over 80 characters
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/host/pcie-designware.c

@@ -220,7 +220,7 @@ static void clear_irq_range(struct pcie_port *pp, unsigned int irq_base,
 	for (i = 0; i < nvec; i++) {
 		irq_set_msi_desc_off(irq_base, i, NULL);
 		clear_bit(pos + i, pp->msi_irq_in_use);
-		/* Disable corresponding interrupt on MSI interrupt controller */
+		/* Disable corresponding interrupt on MSI controller */
 		res = ((pos + i) / 32) * 12;
 		bit = (pos + i) % 32;
 		dw_pcie_rd_own_conf(pp, PCIE_MSI_INTR0_ENABLE + res, 4, &val);