Fix "strace -oFILE -ff -p<nonexistant_pid>" behavior

Fix "strace -oFILE -ff -p<nonexistant_pid>" behavior

* strace.c (newoutf): Set tcp->outf in non-ff mode too.
(alloctcb): This define is removed.
(alloc_tcb): Renamed to alloctcb. Does not set tcp->outf anymore.
Lost 'command_options_parsed' flag parameter.
(startup_attach): Do not say "interrupt to quit" in attach message -
^C does not work in all cases, we mislead users.
Call newoutf(tcp) after successful attach.
(startup_child): Call newoutf(tcp) after successful attach.
(trace): Call newoutf(tcp) when we picked up already attached child.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>