Make the __stack_chk_fail message more searchable on the internets.

Noticed while writing documentation:

  https://source.android.com/devices/tech/debug/

Bug: http://b/28746168
Test: crasher
Change-Id: Ied1c1b1c75a85a899f07e6927134b9bf91316fe4
diff --git a/libc/bionic/__stack_chk_fail.cpp b/libc/bionic/__stack_chk_fail.cpp
index 6e052e3..cb039cf 100644
--- a/libc/bionic/__stack_chk_fail.cpp
+++ b/libc/bionic/__stack_chk_fail.cpp
@@ -32,5 +32,5 @@
 #include "private/libc_logging.h"
 
 void __stack_chk_fail() {
-  __libc_fatal("stack corruption detected");
+  __libc_fatal("stack corruption detected (-fstack-protector)");
 }