syscalls/setpriority02: Reconstruct && Convert to new API

* merge setpriority03, 04 and 05 into setpriority02
* add test for EACCES with PRIO_PGRP flag
* add tests for ESRCH with PRIO_PGRP and PRIO_USER flag

Signed-off-by: Guangwen Feng <fenggw-fnst@cn.fujitsu.com>
Signed-off-by: Cyril Hrubis <chrubis@suse.cz>
8 files changed