xen/arm: p2m_init and p2m_lock should be static

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

arch/arm/xen/p2m.c

@@ -25,7 +25,7 @@ struct xen_p2m_entry {
 	struct rb_node rbnode_phys;
 };
 
-rwlock_t p2m_lock;
+static rwlock_t p2m_lock;
 struct rb_root phys_to_mach = RB_ROOT;
 EXPORT_SYMBOL_GPL(phys_to_mach);
 static struct rb_root mach_to_phys = RB_ROOT;
@@ -201,7 +201,7 @@ bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn)
 }
 EXPORT_SYMBOL_GPL(__set_phys_to_machine);
 
-int p2m_init(void)
+static int p2m_init(void)
 {
 	rwlock_init(&p2m_lock);
 	return 0;