Revert "adb: add support for O_CLOEXEC to unique_fd pipe wrapper."

This reverts commit ffa58c29421e4d341d8e6b743a23985bc7b8dd0b.

Reason for revert: mac doesn't have pipe2

Change-Id: Id6a517bb500cbea602839f06452bc5e6d92289f1
1 file changed