netmap: Remove obsolete compatibility defines

[markj]

Summary

No functional change intended.

sys/dev/netmap/netmap_freebsd.c

if (((*mres)->flags & PG_FICTITIOUS) != 0) {
                  */
                 page = *mres;
                 vm_page_updatefake(page, paddr, memattr);
         } else {
                 /*
                  * Replace the passed in reqpage page with our own fake page and
                  * free up the all of the original pages.
                  */
-#ifndef VM_OBJECT_WUNLOCK       /* FreeBSD < 10.x */
-#define VM_OBJECT_WUNLOCK VM_OBJECT_UNLOCK
-#define VM_OBJECT_WLOCK VM_OBJECT_LOCK
-#endif /* VM_OBJECT_WUNLOCK */
-
                 VM_OBJECT_WUNLOCK(object);
                 page = vm_page_getfake(paddr, memattr);
                 VM_OBJECT_WLOCK(object);
                 vm_page_replace(page, object, (*mres)->pindex, *mres);
                 *mres = page;
         }
         page->valid = VM_PAGE_BITS_ALL;
         return (VM_PAGER_OK);