split cap_mmap_addr() out of cap_file_mmap()

... switch callers.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index fa2341b..25c125e 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3104,7 +3104,7 @@
 	}
 
 	/* do DAC check on address space usage */
-	rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
+	rc = cap_mmap_addr(addr);
 	if (rc || addr_only)
 		return rc;