Copy the produced .dll files to fuzz/ as well (Cygwin & mingw)

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from openssl#5759)

Author: levitte

Configurations/unix-Makefile.tmpl

@@ -927,8 +927,10 @@ EOF
 	  . (windowsdll() ? <<"EOF" : "");
 	rm -f apps/$shlib$shlibext
 	rm -f test/$shlib$shlibext
+	rm -f fuzz/$shlib$shlibext
 	cp -p $shlib$shlibext apps/
 	cp -p $shlib$shlibext test/
+	cp -p $shlib$shlibext fuzz/
 EOF
   }
   sub obj2dso {