* exceptions.cc (signal_fixup_after_exec): Eliminate argument in definition.
Don't reset signal handlers after spawm. Just treat like fork/exec.
* dcrt0.cc (dll_crt0_1): Don't pass PROC_SPAWN argument to
signal_fixup_after_exec.
* syscalls.cc (unlink): Don't change attributes of file if not readonly/system.
Ditto for resetting of arguments.