scripts: gen-dependencies.sh: fix kmod dependency generation

Do not output faulty ".ko" dependency if a scanned .ko file has an empty
"depends=" specification, also replace the `grep | sed | awk` chain with a
single sed program.

Signed-off-by: Jo-Philipp Wich <jow@openwrt.org>

SVN-Revision: 44206

scripts/gen-dependencies.sh

@@ -28,8 +28,6 @@ tmp=`mktemp $TMP_DIR/dep.XXXXXXXX`
 for kmod in `find $TARGETS -type f -name \*.ko`; do
 	$OBJCOPY -O binary -j .modinfo $kmod $tmp
 	sed -e 's,\x00,\n,g' $tmp | \
-		egrep -a '^depends=' | \
-		sed -e 's,^depends=,,' -e 's/,/\n/g' | \
-		awk '{ print $1 ".ko" }'
+		sed -ne '/^depends=.\+/ { s/^depends=//; s/\(,\|$\)/.ko\n/gp; q }'
 done | sort -u
 rm -f $tmp