sed(1) -i option broken, all output send stdout and original file is empty

[Takehiko NOZAKI]

bonehead in <<cset:57ae82b6278a5085c53aa59e19c96bccf12de829>>

forgot to merge following process.c change

https://svnweb.freebsd.org/base/head/usr.bin/sed/process.c?r1=122049&r2=122048&pathrev=122049

[Takehiko NOZAKI]

BUGFIX: Issue #256 - sed(1) -i option broken, all output send stdout and original file is empty

→ <<cset added7000cc3>>