testsuite: suppress usage of setjmp in a testcode (rule 21_4-a)

According to the rule MISRAC-2012 21.4.a the standard header
file <setjmp.h> shall not be used. Suppress it, because it raises
violation in a testcode, not in a runtime code.
Tag suppresses reporting of violation for the current file,
starting from the line where the suppression is located.
It is a deliberate deviation.

Found as a coding guideline violation (MISRA R21.4.a) by static
coding scanning tool.

Signed-off-by: Maksim Masalski <maksim.masalski@intel.com>