package/slirp4netns: needs TUN support in the kernel

slirp4netns needs a kernel with TUN support, so enable that and the few
options it depends on.

Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
Cc: Raphael Pavlidis <raphael.pavlidis@gmail.com>
Reviewed-by: Raphael Pavlidis <raphael.pavlidis@gmail.com>
Signed-off-by: Julien Olivain <ju.o@free.fr>

package/slirp4netns/slirp4netns.mk

@@ -12,4 +12,13 @@ SLIRP4NETNS_DEPENDENCIES = libcap libglib2 libseccomp slirp
 
 SLIRP4NETNS_AUTORECONF = YES
 
+define SLIRP4NETNS_LINUX_CONFIG_FIXUPS
+	$(call KCONFIG_ENABLE_OPT,CONFIG_NET)
+	$(call KCONFIG_ENABLE_OPT,CONFIG_NET_CORE)
+	$(call KCONFIG_ENABLE_OPT,CONFIG_NETDEVICES)
+	$(call KCONFIG_ENABLE_OPT,CONFIG_NET_CORE)
+	$(call KCONFIG_ENABLE_OPT,CONFIG_INET)
+	$(call KCONFIG_ENABLE_OPT,CONFIG_TUN)
+endef
+
 $(eval $(autotools-package))