Fixed two non-standard usages of sem_open in the libFuzzer library and
one NetBSD-related modification with test script.
- The return value to indicate error should be SEM_FAILED instead of (void *)-1 (please refer to "RETURN VALUE" section in this page). Actually, SEM_FAILED != (void *)-1 holds in NetBSD.
- The SharedMemoryRegion::SemName function should return name starting with slash. Because the behaviour of name which does not start with slash is unspecified as the "DESCRIPTION" section specified:
If name does not begin with the <slash> character, the effect is implementation-defined.
- The length of name is limited to 14 in NetBSD, it is suggested to reduce the length of equivalence server name in the test script.