component/openssl: fix perl binary used during compilation

Since openssl 3.0, Config.pm is lauched with shebang "/usr/bin/env perl"
so perl from slapos must be in the PATH.

component/openssl/buildout.cfg

@@ -42,7 +42,7 @@ make-targets =
     ln -sfv $i ${:certs}/`${:location}/bin/openssl x509 -hash -noout -in $i`.0
   ; done
 environment =
-  PERL=${perl:location}/bin/perl
+  PATH=${perl:location}/bin:%(PATH)s
 
 [openssl-3.0]
 <= openssl-common