global: convert indentation-TABs to spaces

Transformed via this shell code:
t=$'\t'
git ls-files \
  | grep -vE '(^|/)((GNU)?[Mm]akefile|ChangeLog)|\.(am|mk)$' \
  | grep -vE 'tests/pr/|help2man' \
  | xargs grep -lE "^ *$t" \
  | xargs perl -MText::Tabs -ni -le \
    '$m=/^( *\t[ \t]*)(.*)/; print $m ? expand($1) . $2 : $_'

tests/misc/help-version

@@ -77,11 +77,11 @@ for lang in C fr da; do
       eval "expected=\$expected_failure_status_$prog"
       test x$expected = x && expected=1
       if test $status = $expected; then
-	: # ok
+        : # ok
       else
-	fail=1
-	echo "*** $i: bad exit status \`$status' (expected $expected)," 1>&2
-	echo "  with --help or --version output redirected to /dev/full" 1>&2
+        fail=1
+        echo "*** $i: bad exit status \`$status' (expected $expected)," 1>&2
+        echo "  with --help or --version output redirected to /dev/full" 1>&2
       fi
     fi
   done