net: Remove an unmatched unlock of ForkLock
net: Remove an unmatched unlock of ForkLock

Remove an RUnlock of syscall.ForkLock with no matching RLock.
Holding ForkLock in netFD.dup is unnecessary: dupCloseOnExecOld
locks and unlocks the lock on its own and dupCloseOnExec doesn't
need the ForkLock to be held.

LGTM=iant
R=golang-codereviews, bradfitz, iant
CC=golang-codereviews
https://codereview.appspot.com/99800044

Committer: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@golang.org>

h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang