xen/apic/xenbus/swiotlb/pcifront/grant/tmem: Make functions or variables static.

There is no need for those functions/variables to be visible. Make them
static and also fix the compile warnings of this sort:

drivers/xen/<some file>.c: warning: symbol '<blah>' was not declared. Should it be static?

Some of them just require including the header file that
declares the functions.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
diff --git a/arch/x86/xen/apic.c b/arch/x86/xen/apic.c
index ec57bd3..7005ced 100644
--- a/arch/x86/xen/apic.c
+++ b/arch/x86/xen/apic.c
@@ -6,8 +6,9 @@
 
 #include <xen/xen.h>
 #include <xen/interface/physdev.h>
+#include "xen-ops.h"
 
-unsigned int xen_io_apic_read(unsigned apic, unsigned reg)
+static unsigned int xen_io_apic_read(unsigned apic, unsigned reg)
 {
 	struct physdev_apic apic_op;
 	int ret;
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index ff962d4..cb1b191 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -79,6 +79,8 @@
 #include "smp.h"
 #include "multicalls.h"
 
+#include <xen/events.h>
+
 EXPORT_SYMBOL_GPL(hypercall_page);
 
 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
diff --git a/arch/x86/xen/pci-swiotlb-xen.c b/arch/x86/xen/pci-swiotlb-xen.c
index 967633a..2d58b3f 100644
--- a/arch/x86/xen/pci-swiotlb-xen.c
+++ b/arch/x86/xen/pci-swiotlb-xen.c
@@ -8,6 +8,7 @@
 #include <xen/xen.h>
 #include <asm/iommu_table.h>
 
+#include <asm/xen/swiotlb-xen.h>
 int xen_swiotlb __read_mostly;
 
 static struct dma_map_ops xen_swiotlb_dma_ops = {
diff --git a/arch/x86/xen/platform-pci-unplug.c b/arch/x86/xen/platform-pci-unplug.c
index ffcf261..0a78524 100644
--- a/arch/x86/xen/platform-pci-unplug.c
+++ b/arch/x86/xen/platform-pci-unplug.c
@@ -24,6 +24,7 @@
 #include <linux/module.h>
 
 #include <xen/platform_pci.h>
+#include "xen-ops.h"
 
 #define XEN_PLATFORM_ERR_MAGIC -1
 #define XEN_PLATFORM_ERR_PROTOCOL -2