t-prio-queue: simplify using compound literals

t-prio-queue: simplify using compound literals

Test names like "basic" are mentioned seven times in the code (ignoring
case): Twice when defining the input and result macros, thrice when
defining the test function, and twice again when calling it.  Reduce
that to a single time by using compound literals to pass the input and
result arrays via TEST_INPUT to test_prio_queue().

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>