i2c: Add module.h to modular files prev. implicitly getting it

These files use interfaces from linux/module.h, so they must
include that file to avoid build errors when the implicit
presence of module.h is removed.

[with i2c-pxa-pci.c fix from Randy Dunlap <rdunlap@xenotime.net>]

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/drivers/i2c/busses/i2c-pxa-pci.c b/drivers/i2c/busses/i2c-pxa-pci.c
index b73da6c..632e088 100644
--- a/drivers/i2c/busses/i2c-pxa-pci.c
+++ b/drivers/i2c/busses/i2c-pxa-pci.c
@@ -3,6 +3,7 @@
  * It does not support slave mode, the register slightly moved. This PCI
  * device provides three bars, every contains a single I2C controller.
  */
+#include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/platform_device.h>
 #include <linux/i2c/pxa-i2c.h>