hints/netbsd.sh: prevent noise when checking for --whole-archive

https://www.nntp.perl.org/group/perl.perl5.porters/2024/04/msg268141.html

hints/netbsd.sh

@@ -40,8 +40,8 @@ case "$osvers" in
 # gcc 4.6 doesn't support --whole-archive, but it's required for the
 # system gcc to build correctly, so check for it
 echo 'int f(void) { return 0; }' >try.c
-if ${cc:-cc} $cccdlflags -c try.c -otry.o 2>&1 &&
-   ${cc:-cc} --whole-archive $lddlflags try.o -otry.so 2>&1 ; then
+if ${cc:-cc} $cccdlflags -c try.c -otry.o >/dev/null 2>&1 &&
+   ${cc:-cc} --whole-archive $lddlflags try.o -otry.so >/dev/null 2>&1 ; then
     lddlflags="--whole-archive $lddlflags"
 fi
 rm try.c try.o try.so 2>/dev/null