We have a few remaining tests where ztest module is not used directly,
and instead lower-level tc_util.h is used (where ztest also uses that
header). Supposedly, there're good reasons for that. However, tc_util.h
tests have output which is somewhat inconsistent with ztest output,
which may be a problem with automated parsing of test results, e.g. in
CI systems.
So, factor out code to mark testsuite start/end from ztest.c to
tc_util.h as TC_SUITE_START() and TC_SUITE_END() macros, to allow
tc_util.h based tests to produce output fully consistent with
ztest, while avoiding duplicate of code. TC_SUITE_END() accepts
result code (TC_PASS/TC_FAIL), similar to existing TC_END_REPORT().
Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>