Tests with --force-enable must not SKIP because of missing Valgrind

[Tomasz Gromadzki]

ISSUE: Tests with --force-enable must not SKIP because of missing Valgrind

Environment Information

• PMDK package version(s):
• OS(es) version(s):
• ndctl version(s):
• kernel version(s):
• compiler, libraries, packaging and other related tools version(s):

Please provide a reproduction of the bug:

https://github.com/pmem/pmdk/actions/runs/5456035358/jobs/9928286689#step:6:1
https://github.com/pmem/pmdk/actions/runs/5456035358/jobs/9928290346#step:6:7

How often bug is revealed: (always, often, rare):

always

Actual behavior:

Valgrind tests silently skip if Valgrind is not installed.
https://github.com/pmem/pmdk/actions/runs/5456035358/jobs/9928286689#step:6:9

Expected behavior:

Test with --force-enable shall not skip at all. It should fail.

• either disable SKIP in case force-enable or RUNTEST.[sh|py] should fail if run with --force-enable, but no Valgrind is detected
  Requested priority: (Showstopper, High, Medium, Low) High