xen: Clean up map cache API naming

The map cache is a Xen thing, so its API should make this clear.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/xen-mapcache.h b/xen-mapcache.h
index 6216cc3..606b8af 100644
--- a/xen-mapcache.h
+++ b/xen-mapcache.h
@@ -9,13 +9,11 @@
 #ifndef XEN_MAPCACHE_H
 #define XEN_MAPCACHE_H
 
-void     qemu_map_cache_init(void);
-uint8_t  *qemu_map_cache(target_phys_addr_t phys_addr, target_phys_addr_t size, uint8_t lock);
-ram_addr_t qemu_ram_addr_from_mapcache(void *ptr);
-void     qemu_invalidate_entry(uint8_t *buffer);
-void     qemu_invalidate_map_cache(void);
-
-#define mapcache_lock()   ((void)0)
-#define mapcache_unlock() ((void)0)
+void xen_map_cache_init(void);
+uint8_t *xen_map_cache(target_phys_addr_t phys_addr, target_phys_addr_t size,
+                       uint8_t lock);
+ram_addr_t xen_ram_addr_from_mapcache(void *ptr);
+void xen_invalidate_map_cache_entry(uint8_t *buffer);
+void xen_invalidate_map_cache(void);
 
 #endif /* !XEN_MAPCACHE_H */