Fixed Feature/WriteCov.c test for llvm-lit (LLVM >= 3.0). The test is
now broken for DejaGNU.
Fixed Runtime/POSIX/FD_Fail2.c for llvm-lit (LLVM >= 3.0). This test
is now broken for DejaGNU.
Fixed Runtime/POSIX/FilePerm.c for llvm-lit (LLVM >= 3.0). This test
is now broken under DejaGNU.
Fixed Runtime/POSIX/FreeArgv.c test for llvm-lit (LLVM >= 3.0). The
test has also been improved by checking KLEE's output with FileCheck.

Unfortunately we can't check file error locations because the order
we see errors is not guaranteed.

This test is now broken under DejaGNU.