Port to Solaris 8 perl, which does not support "use warnings;".

* tests/dd/skip-seek: Skip test if "use warnings;" fails.
* tests/du/files0-from: Likewise.
* tests/misc/base64: Likewise.
* tests/misc/basename: Likewise.
* tests/misc/cut: Likewise.
* tests/misc/date: Likewise.
* tests/misc/dircolors: Likewise.
* tests/misc/dirname: Likewise.
* tests/misc/expand: Likewise.
* tests/misc/expr: Likewise.
* tests/misc/factor: Likewise.
* tests/misc/fmt: Likewise.
* tests/misc/fold: Likewise.
* tests/misc/head-elide-tail: Likewise.
* tests/misc/ls-misc: Likewise.
* tests/misc/md5sum: Likewise.
* tests/misc/md5sum-newline: Likewise.
* tests/misc/mktemp: Likewise.
* tests/misc/od: Likewise.
* tests/misc/paste-no-nl: Likewise.
* tests/misc/pr: Likewise.
* tests/misc/seq: Likewise.
* tests/misc/sha1sum: Likewise.
* tests/misc/sha1sum-vec: Likewise.
* tests/misc/sha224sum: Likewise.
* tests/misc/sha256sum: Likewise.
* tests/misc/sha384sum: Likewise.
* tests/misc/sha512sum: Likewise.
* tests/misc/sort-merge: Likewise.
* tests/misc/stat-printf: Likewise.
* tests/misc/sum: Likewise.
* tests/misc/test-diag: Likewise.
* tests/misc/tsort: Likewise.
* tests/misc/unexpand: Likewise.
* tests/misc/wc-files0-from: Likewise.
* tests/misc/xstrtol: Likewise.
* tests/mv/i-1: Likewise.
* tests/rm/empty-name: Likewise.
* tests/rm/unreadable: Likewise.

tests/misc/expr

@@ -20,7 +20,7 @@
 : ${PERL=perl}
 : ${srcdir=.}
 
-$PERL -e 1 > /dev/null 2>&1 || {
+$PERL -e 'use warnings;' > /dev/null 2>&1 || {
   echo 1>&2 "$0: configure didn't find a usable version of Perl," \
     "so can't run this test"
   exit 77