The two test cases dgemv_tester and dgemm_tester accept the degree of
concurrency as command line argument (amongst others). Fail early if
value 0 has been specified, instead of later with less-clear symptoms.
Signed-off-by: Marius Hillenbrand <mhillen@linux.ibm.com>
... instead of (number of hw threads - 4) to avoid invalid numbers on
smaller systems. Currently, systems with 4 or fewer CPUs (e.g., small CI
VMs) would fail the test. Fixes one of the issues discussed in #2668
Signed-off-by: Marius Hillenbrand <mhillen@linux.ibm.com>