ftrace/selftest: make unresolved cases cause failure if --fail-unresolved set

ftrace/selftest: make unresolved cases cause failure if --fail-unresolved set

BugLink: https://bugs.launchpad.net/bugs/1877958
Currently, ftracetest will return 1 (failure) if any unresolved cases
are encountered.  The unresolved status results from modules and
programs not being available, and as such does not indicate any
issues with ftrace itself.  As such, change the behaviour of
ftracetest in line with unsupported cases; if unsupported cases
happen, ftracetest still returns 0 unless --fail-unsupported.  Here
--fail-unresolved is added and the default is to return 0 if
unresolved results occur.

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
(backported from commit b730d668138cb3dd9ce78f8003986d1adae5523a)
[PHLin: context adjustment]
Signed-off-by: Po-Hsu Lin <po-hsu.lin@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Kleber Souza <kleber.souza@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>