examples/bond: fix invalid use of trylock

examples/bond: fix invalid use of trylock

The conditional rte_spinlock_trylock() was used as if it is an
unconditional lock operation in a number of places.

Fixes: cc7e8ae84faa ("examples/bond: add example application for link bonding mode 6")
Cc: stable@dpdk.org
Signed-off-by: Mattias Rönnblom <mattias.ronnblom@ericsson.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
Acked-by: Min Hu (Connor) <humin29@huawei.com>
Acked-by: Tyler Retzlaff <roretzla@linux.microsoft.com>