This source file was copied from libbsd, use the system library instead

--- a/third_party/libsync/BUILD.gn	2022-06-21 21:52:53.867987945 +0200
+++ a/third_party/libsync/BUILD.gn	2022-06-28 17:30:45.327377489 +0200
@@ -21,9 +21,8 @@
     ]
   }
 
-  config("libsync_private_config") {
-    # To suppress the warning caused by strlcpy.
-    cflags = [ "-Wno-implicit-function-declaration" ]
+  pkg_config("libsync_private_config") {
+    packages = [ "libbsd-overlay" ]
   }
 
   source_set("libsync") {
@@ -31,7 +30,6 @@
       "src/include/sync/sync.h",
       "src/sw_sync.h",
       "src/sync.c",
-      "strlcpy.c",
     ]
 
     configs -= [ "//build/config/compiler:chromium_code" ]