dnsmasq: add DHCP build switch support in full variant

Add config option which allows to enable/disable DHCP support at compile
time. Make DHCPv6 support dependant on DHCP support as DHCPv6 support
implies having DHCP support.

Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>

package/network/services/dnsmasq/Makefile

@@ -23,7 +23,8 @@ PKG_BUILD_DIR:=$(BUILD_DIR)/$(PKG_NAME)-$(BUILD_VARIANT)/$(PKG_NAME)-$(PKG_VERSI
 
 PKG_INSTALL:=1
 PKG_BUILD_PARALLEL:=1
-PKG_CONFIG_DEPENDS:=CONFIG_PACKAGE_dnsmasq_$(BUILD_VARIANT)_dhcpv6 \
+PKG_CONFIG_DEPENDS:= CONFIG_PACKAGE_dnsmasq_$(BUILD_VARIANT)_dhcp \
+	CONFIG_PACKAGE_dnsmasq_$(BUILD_VARIANT)_dhcpv6 \
 	CONFIG_PACKAGE_dnsmasq_$(BUILD_VARIANT)_dnssec \
 	CONFIG_PACKAGE_dnsmasq_$(BUILD_VARIANT)_auth \
 	CONFIG_PACKAGE_dnsmasq_$(BUILD_VARIANT)_ipset \
@@ -76,8 +77,8 @@ endef
 define Package/dnsmasq-full/description
 $(call Package/dnsmasq/description)
 
-This is a fully configurable variant with DHCPv6, DNSSEC, Authoritative DNS and
-IPset, Conntrack support & NO_ID enabled by default.
+This is a fully configurable variant with DHCPv4, DHCPv6, DNSSEC, Authoritative DNS
+and IPset, Conntrack support & NO_ID enabled by default.
 endef
 
 define Package/dnsmasq/conffiles
@@ -87,9 +88,12 @@ endef
 
 define Package/dnsmasq-full/config
 	if PACKAGE_dnsmasq-full
+	config PACKAGE_dnsmasq_full_dhcp
+		bool "Build with DHCP support."
+		default y
 	config PACKAGE_dnsmasq_full_dhcpv6
 		bool "Build with DHCPv6 support."
-		depends on IPV6
+		depends on IPV6 && PACKAGE_dnsmasq_full_dhcp
 		default y
 	config PACKAGE_dnsmasq_full_dnssec
 		bool "Build with DNSSEC support."
@@ -125,7 +129,8 @@ ifeq ($(BUILD_VARIANT),nodhcpv6)
 endif
 
 ifeq ($(BUILD_VARIANT),full)
-	COPTS += $(if $(CONFIG_PACKAGE_dnsmasq_$(BUILD_VARIANT)_dhcpv6),,-DNO_DHCP6) \
+	COPTS += $(if $(CONFIG_PACKAGE_dnsmasq_$(BUILD_VARIANT)_dhcp),,-DNO_DHCP) \
+		$(if $(CONFIG_PACKAGE_dnsmasq_$(BUILD_VARIANT)_dhcpv6),,-DNO_DHCP6) \
 		$(if $(CONFIG_PACKAGE_dnsmasq_$(BUILD_VARIANT)_dnssec),-DHAVE_DNSSEC) \
 		$(if $(CONFIG_PACKAGE_dnsmasq_$(BUILD_VARIANT)_auth),,-DNO_AUTH) \
 		$(if $(CONFIG_PACKAGE_dnsmasq_$(BUILD_VARIANT)_ipset),,-DNO_IPSET) \