Add copy_file_range(2) syscall stub to bionic.

Test: treehugger
Bug: https://buganizer.corp.google.com/issues/227784687
Change-Id: I543306cd2234189401bf7c9d80d405eeb6e4d41d
diff --git a/libc/libc.map.txt b/libc/libc.map.txt
index e64fe00..79f331a 100644
--- a/libc/libc.map.txt
+++ b/libc/libc.map.txt
@@ -1579,6 +1579,7 @@
 LIBC_U { # introduced=UpsideDownCake
   global:
     close_range;
+    copy_file_range;
 } LIBC_T;
 
 LIBC_PRIVATE {