Merge "Fix build for compiler update." am: d341fba5dc am: e976ea55be

Original change: https://android-review.googlesource.com/c/platform/external/ppp/+/1790958

Change-Id: I51a6591227a6a77fc6f399597d5312232c477b82
diff --git a/pppd/sys-linux.c b/pppd/sys-linux.c
index d5dbc7c..4fbcca9 100644
--- a/pppd/sys-linux.c
+++ b/pppd/sys-linux.c
@@ -1044,7 +1044,7 @@
  * output - Output PPP packet.
  */
 
-void output (int unit, unsigned char *p, int len)
+__attribute((weak)) void output (int unit, unsigned char *p, int len)
 {
     int fd = ppp_fd;
     int proto;