fff-wireguard: Adapt for renamed OpenWrt wireguard packages

Because wireguard is part of the Linux kernel starting with version 5.6,
the wireguard packages have been renamed upstream.

Update our dependencies to match this.

This fixes build for the layer3 variant.

Signed-off-by: Fabian Bläse <fabian@blaese.de>
Reviewed-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
[add fix comment]
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>

src/packages/fff/fff-wireguard/Makefile

@@ -1,7 +1,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=fff-wireguard
-PKG_RELEASE:=6
+PKG_RELEASE:=7
 
 include $(INCLUDE_DIR)/package.mk
 
@@ -11,8 +11,9 @@ define Package/fff-wireguard
 	TITLE:=Freifunk-Franken wireguard
 	URL:=https://www.freifunk-franken.de
 	DEPENDS:= \
+		+kmod-wireguard \
 		+owipcalc \
-		+wireguard \
+		+wireguard-tools \
 		+fff-babeld \
 		+fff-network
 endef