More reliable `gettimeofday` detection.
More reliable `gettimeofday` detection.

`src/Platforms/Gcc/UTestPlatform.cpp:38` relies on it being defined in
`sys/time.h` but that header is not present with TI-CGT-ARM despite
the test succeeding.

Updated the adjacent tests with the same problem.

offa/cpputest,cpputest/cpputest,basvodde/cpputest,cpputest/cpputest,cpputest/cpputest,offa/cpputest,offa/cpputest,basvodde/cpputest,cpputest/cpputest,basvodde/cpputest,offa/cpputest,basvodde/cpputest