tests: Remove bogus test for unsorted file listing

Minimized from what Debian applies:
https://git.hadrons.org/cgit/debian/pkgs/inetutils.git/tree/debian/patches/local/0006-tests-Remove-bogus-test-for-unsorted-file-listing.patch?id=8ab7f49fe5cf194e989ae6ae6a78eb65397c5778
--- a/tests/libls.sh
+++ b/tests/libls.sh
@@ -91,1 +91,0 @@
-REPLY_Cf=`$LS -Cf $LSDIR`
@@ -130,3 +129,0 @@
-test x"$REPLY_C" != x"$REPLY_Cf" ||
-  { errno=1; echo >&2 'Failed to disable sorting with "-f".'; }
-