Linux's sendfile() returns 0 when remote has closed connection. Convert it to EPIPE.
Linux's sendfile() returns 0 when remote has closed connection. Convert it
to EPIPE.

Distrotech/dovecot,damoxc/dovecot,damoxc/dovecot,damoxc/dovecot,Distrotech/dovecot,damoxc/dovecot,Distrotech/dovecot,Distrotech/dovecot,damoxc/dovecot,Distrotech/dovecot