Ensure correct NetBSD sources checkout

Previously, under some circumstances, the make command could
yield netbsdsrc in other directories than the source directory,
as expected.

This patch fixes this behaviour, by first changing to the expected
directory, and only at the end going back to the original directory.

releasetools/Makefile

@@ -111,15 +111,18 @@ install:
 # download and update NetBSD reference sources.
 nbsd_fetch:
 	export CVS_RSH=ssh; 							\
+	export OLDPWD=`pwd`;							\
 	echo "retrieving hierarchies from ${NBSD_CVSROOT}";			\
 	IFS=,;									\
-	cat nbsd_ports | grep -v '^#' | while read port ;			\
+	cd ..;									\
+	cat releasetools/nbsd_ports | grep -v '^#' | while read port ;		\
 	do	set $$port;							\
 		date=$$1; minixpath=$$2; origpath=$$3;				\
 		if [ $$# -lt 3 ]; then origpath=$$2; fi;			\
 		echo "retrieving $$origpath ..";				\
-		cd .. && cvs -q -d ${NBSD_CVSROOT} co -N -D "$$date UTC" -d nbsdsrc "src/$$origpath" ; \
-	done
+		cvs -q -d ${NBSD_CVSROOT} co -N -D "$$date UTC" -d nbsdsrc "src/$$origpath" ; \
+	done;									\
+	cd $${OLDPWD};
 
 nbsd_diff:
 	find .. -name minix-port.patch | xargs rm