tests: fix tests for 055086f (well-known attr check)

tests: fix tests for 055086f (well-known attr check)

Fix tests/aspathtest.c by including an ORIGIN attribute in the
testcases.  After 055086f "bgpd: well-known attr check only run for
v4/uni, which could cause a crash," we're now checking for it and tests
are failing due to that.

Note that test #11 ("4b AS4_PATH w/o AS_PATH") is no longer accepted as
OK since the function now checks for the existence of an AS_PATH attr.

Fixes: 055086f ("bgpd: well-known attr check only run for v4/uni"...)
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
(cherry picked from commit c68f6d9dbb9f910d3ee82e099655fff7c12ef856)