spi: dw-pci: fix bug when regs left uninitialized

The commit 04f421e7 "spi: dw: use managed resources" changes drivers to use
managed functions, but seems wasn't properly tested in PCI case. The regs field
of struct dw_spi left uninitialized. Thus, kernel crashes when tries to access
to the SPI controller registers. This patch fixes the issue.

Fixes: 04f421e7 (spi: dw: use managed resources)
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Cc: stable@vger.kernel.org
diff --git a/drivers/spi/spi-dw-pci.c b/drivers/spi/spi-dw-pci.c
index 3f3dc12..e149604 100644
--- a/drivers/spi/spi-dw-pci.c
+++ b/drivers/spi/spi-dw-pci.c
@@ -62,6 +62,8 @@
 	if (ret)
 		return ret;
 
+	dws->regs = pcim_iomap_table(pdev)[pci_bar];
+
 	dws->bus_num = 0;
 	dws->num_cs = 4;
 	dws->irq = pdev->irq;