This call to os.Getwd (or getwd) has been part of the linker since the C
implementation in 7d507dc6. It stopped being used in 26438d4d, and
survived the conversion to Go in 1f9dbb60.

Its return value goes unused (the linker gets the value for AT_comp_dir in
dwarf.go), remove it.

Change-Id: I3d4594813bb4ee0a6af31a36e19d99ec4b863677
Reviewed-on: https://go-review.googlesource.com/19655Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>