dropbear: fix missing directory with systemd

The current SysV startup script create a directory which is necessary
for dropbear to correctly work.
This creation is not done with systemd.

Instead of both init creating the directory, we add the creation of this
directory to the INSTALL_TARGET_CMDS to make sure it's present.

[Peter: use make syntax for TARGET_DIR as pointed out by Thomas]
Signed-off-by: Maxime Hadjinlian <maxime.hadjinlian@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/dropbear/S50dropbear

@@ -10,10 +10,6 @@ start() {
 	DROPBEAR_ARGS="$DROPBEAR_ARGS -R"
 
 	echo -n "Starting dropbear sshd: "
-	# Make sure dropbear directory exists
-	if [ ! -d /etc/dropbear ] ; then
-		mkdir -p /etc/dropbear
-	fi
 	umask 077
 	start-stop-daemon -S -q -p /var/run/dropbear.pid \
 		--exec /usr/sbin/dropbear -- $DROPBEAR_ARGS

package/dropbear/dropbear.mk

@@ -85,6 +85,7 @@ define DROPBEAR_INSTALL_TARGET_CMDS
 	for f in $(DROPBEAR_TARGET_BINS); do \
 		ln -snf ../sbin/dropbear $(TARGET_DIR)/usr/bin/$$f ; \
 	done
+	mkdir -p $(TARGET_DIR)/etc/dropbear
 endef
 
 $(eval $(autotools-package))