Don't execute scripts without '#!' marker through /bin/sh. This reflects the change done in glibc through <https://sourceware.org/bugzilla/show_bug.cgi?id=13134> and <https://sourceware.org/git/?p=glibc.git;a=commitdiff;h=d96de9634a334af16c0ac711074c15ac1762b23c>. * lib/spawni.c (internal_function): Remove macro. (script_execute): Remove function. (__spawni): Don't invoke script_execute. * lib/execute.c (execute): Disable the ENOEXEC handling. * lib/spawn-pipe.c (create_pipe): Likewise. * NEWS: Mention the change.