tests: sort: avoid a false failure on very slow systems

* tests/sort/sort-NaN-infloop.sh: Up the timeout to about 240x
a "standard" system, as this was seen to timeout on a
mipsel VM using QEMU emulation.
Reported by Bruno Haible.

tests/sort/sort-NaN-infloop.sh

@@ -22,10 +22,10 @@ print_ver_ sort
 echo nan > F || framework_failure_
 printf 'nan\nnan\n' > exp || framework_failure_
 timeout 10 sort -g -m F F > out || fail=1
-
-# This was seen to infloop on some systems until coreutils v9.2 (bug 55212)
-yes nan | head -n128095 | timeout 60 sort -g > /dev/null || fail=1
-
 compare exp out || fail=1
 
+# This was seen to infloop on some systems until coreutils v9.2 (bug 55212)
+yes nan | head -n128095 | timeout 120 sort -g > /dev/null || fail=1
+
+
 Exit $fail