tests: add sched_get_priority_mxx.test

* tests/sched_get_priority_mxx.c: New file.
* tests/sched_get_priority_mxx.test: New test.
* tests/.gitignore: Add sched_get_priority_mxx.
* tests/Makefile.am (check_PROGRAMS): Likewise.
(TESTS): Add sched_get_priority_mxx.test.
diff --git a/tests/Makefile.am b/tests/Makefile.am
index f6d1c82..17f9c90 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -143,6 +143,7 @@
 	rt_sigsuspend \
 	rt_sigtimedwait \
 	rt_tgsigqueueinfo \
+	sched_get_priority_mxx \
 	sched_xetaffinity \
 	sched_xetattr \
 	scm_rights \
@@ -308,6 +309,7 @@
 	rt_sigsuspend.test \
 	rt_sigtimedwait.test \
 	rt_tgsigqueueinfo.test \
+	sched_get_priority_mxx.test \
 	sched_xetaffinity.test \
 	sched_xetattr.test \
 	scm_rights-fd.test \