dev-libs/appstream: keyword on ~ppc64

dev-libs/appstream: keyword on ~ppc64

1/7 as-test_basic                           OK       0.03 s
2/7 as-test_xml                             OK       0.03 s
3/7 as-test_yaml                            OK       0.04 s
4/7 as-test_pool                            OK       0.09 s
5/7 as-test_validate                        OK       0.03 s
6/7 as-test_perf                            OK       0.03 s
7/7 as-test_misc                            OK       0.02 s

Ok:                    7
Expected Fail:         0
Fail:                  0
Unexpected Pass:       0
Skipped:               0
Timeout:               0
Package-Manager: Portage-2.3.85, Repoman-2.3.20
Signed-off-by: Georgy Yakovlev <gyakovlev@gentoo.org>