Assert that the number of subsystems doesn't become negative in
subsystem_sort_test_depends_on_single().
This also fixes a GCC 7 warning about a possible snprintf() truncation
now that the range of i is known to be [1,4].
Change-Id: Idaf8ceab149ff5d786f614f790a8706cae759d38
Signed-off-by: Daniel Verkamp <daniel.verkamp@intel.com>
Reviewed-on: https://review.gerrithub.io/363496
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
0d6f812c8f