unpack: remove backward compat for bug #376741

This case is extremely rare, since the most common practice is to
unpack source files that are already in the cwd. The only Gentoo
packages that needed to be fixed were games-arcade/tuxpuck and
www-plugins/google-talkplugin.
diff --git a/bin/ebuild.sh b/bin/ebuild.sh
index 3d4d557..d68e54b 100755
--- a/bin/ebuild.sh
+++ b/bin/ebuild.sh
@@ -373,18 +373,6 @@
 				local cwd_dest=${x##*/}
 				cwd_dest=${cwd_dest%.*}
 				$1 -c -- "${srcdir}${x}" > "${cwd_dest}" || die "$myfail"
-				case "$EAPI" in
-					0|1|2|3|4|4-python)
-						# If the source file is in a writable directory then
-						# create a symlink for backward-compatible emulation
-						# of tools like gunzip and bunzip2 (see bug #376741).
-						if [[ ! -e ${x%.*} && -w ${x%/*} ]] && \
-							[[ ${x} == "${PORTAGE_BUILDDIR}/"* ||
-							${x} == ./* || ${x} != /* ]] ; then
-							ln -snf "${PWD}/${cwd_dest}" "${x%.*}"
-						fi
-						;;
-				esac
 			fi
 		}