spi: Add module.h to implicit users in drivers/spi

We are clipping down the presence of module.h, since it was
everywhere.  If you really need it, you better call it out,
as per this changeset.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/drivers/spi/spi-pxa2xx-pci.c b/drivers/spi/spi-pxa2xx-pci.c
index 378e504..8caa07d 100644
--- a/drivers/spi/spi-pxa2xx-pci.c
+++ b/drivers/spi/spi-pxa2xx-pci.c
@@ -5,6 +5,7 @@
 #include <linux/pci.h>
 #include <linux/platform_device.h>
 #include <linux/of_device.h>
+#include <linux/module.h>
 #include <linux/spi/pxa2xx_spi.h>
 
 struct ce4100_info {