dropbear: fix service trigger syntax error

The classic single '&' when double '&&' conditional was meant.

Signed-off-by: Kevin Darbyshire-Bryant <kevin@darbyshire-bryant.me.uk>

package/network/services/dropbear/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=dropbear
 PKG_VERSION:=2017.75
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.bz2
 PKG_SOURCE_URL:= \

package/network/services/dropbear/files/dropbear.init

@@ -132,7 +132,7 @@ service_triggers()
 	config_load "${NAME}"
 	config_foreach load_interfaces dropbear
 
-	[ -n "${interfaces}" ] & {
+	[ -n "${interfaces}" ] && {
 		for n in $interfaces ; do
 			procd_add_interface_trigger "interface.*" $n /etc/init.d/dropbear reload
 		done