Change the use of setjmp and longjmp in signalling parameter validation failures
when using the MBEDTLS_CHECK_PARAMS config.h option. This change allows
all calls which might result in a call to the parameter validation failure
handler to always be caught, even without use of the new macros, by placing a
setjmp() in the outer function which calls the test function, which the handler
can jump to.

This has several benefits:
    * it allows us to remove the clang compiler warning (-Wclobbered) caused
      by local auto variables being in the same function as the call to setjmp.
    * removes the need to wrap all function calls in the test functions with the
      TEST_ASSERT() macro. Now all parameter validation function calls should be
      caught.