use /lib not /usr/lib for engines path

--- openssl-1.1.0-pre6/Configurations/unix-Makefile.tmpl~	2016-08-04 17:00:44.000000000 +0300
+++ openssl-1.1.0-pre6/Configurations/unix-Makefile.tmpl	2016-08-06 02:13:21.613568293 +0300
@@ -151,7 +151,7 @@
           our $libdir = $config{libdir} || "lib$multilib";
           $libdir -}
 ENGINESDIR={- use File::Spec::Functions;
-              catdir($prefix,$libdir,"engines-$sover") -}
+              catdir("/",$libdir,"engines-$sover") -}
 
 MANDIR=$(INSTALLTOP)/share/man
 DOCDIR=$(INSTALLTOP)/share/doc/$(BASENAME)