tests/classifier: Make test work in big-endian systems.

Change a test so that the result will be the same in both
little-endian and big-endian systems by editing the test case so that
only one bit differs.

Reported-by: Mijo Safradin <mijo@linux.vnet.ibm.com>
Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>