Added support for /etc/mysql after /etc in the search path for my.cnf

bug #25104


mysys/default.c:
  Added support for /etc/mysql after /etc in the search path for my.cnf

mysys/default.c

@@ -49,6 +49,7 @@ const char *default_directories[]= {
 "sys:/etc/",
 #else
 "/etc/",
+"/etc/mysql/",
 #endif
 #ifdef DATADIR
 DATADIR,