kvm: iommu.c file requires the full module.h present.

This file has things like module_param_named() and MODULE_PARM_DESC()
so it needs the full module.h header present.  Without it, you'll get:

  CC      arch/x86/kvm/../../../virt/kvm/iommu.o
virt/kvm/iommu.c:37: error: expected ‘)’ before ‘bool’
virt/kvm/iommu.c:39: error: expected ‘)’ before string constant
make[3]: *** [arch/x86/kvm/../../../virt/kvm/iommu.o] Error 1
make[2]: *** [arch/x86/kvm] Error 2

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

virt/kvm/iommu.c

@@ -25,6 +25,7 @@
 
 #include <linux/list.h>
 #include <linux/kvm_host.h>
+#include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/stat.h>
 #include <linux/dmar.h>