lang/lua-libmodbus: don't use variables for variables.

PKG_NAME is not to be used as a variable, instead, expanded in all use
cases.

Signed-off-by: Karl Palsson <karlp@etactica.com>

lang/lua-libmodbus/Makefile

@@ -4,8 +4,8 @@ PKG_NAME:=lua-libmodbus
 PKG_VERSION:=0.4.2
 PKG_RELEASE:=1
 
-PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
-PKG_SOURCE_SUBDIR:=$(PKG_NAME)-$(PKG_VERSION)
+PKG_SOURCE:=lua-libmodbus-$(PKG_VERSION).tar.gz
+PKG_SOURCE_SUBDIR:=lua-libmodbus-$(PKG_VERSION)
 PKG_SOURCE_URL:=https://codeload.github.com/remakeelectric/lua-libmodbus/tar.gz/v$(PKG_VERSION)?
 PKG_HASH:=90aff3a2cfe7f91f167ad4ea00f55c2aa86cf2aef93d022e3b2cf906a1791254
 PKG_SOURCE_VERSION:=v$(PKG_VERSION)
@@ -13,20 +13,20 @@ PKG_SOURCE_VERSION:=v$(PKG_VERSION)
 PKG_MAINTAINER:=Karl Palsson <karlp@etactica.com>
 PKG_LICENSE:=MIT
 
-PKG_BUILD_DIR:=$(BUILD_DIR)/$(PKG_NAME)-$(PKG_VERSION)
+PKG_BUILD_DIR:=$(BUILD_DIR)/lua-libmodbus-$(PKG_VERSION)
 
 include $(INCLUDE_DIR)/package.mk
 
-define Package/$(PKG_NAME)
+define Package/lua-libmodbus
   SUBMENU:=Lua
   SECTION:=lang
   CATEGORY:=Languages
-  TITLE:=$(PKG_NAME)
+  TITLE:=lua-libmodbus
   URL:=https://github.com/remakeelectric/lua-libmodbus
   DEPENDS:=+liblua +libmodbus
 endef
 
-define Package/$(PKG_NAME)/description
+define Package/lua-libmodbus/description
 	lua-libmodbus is a binding to libmodbus,
 	see also http://www.libmodbus.org
 endef
@@ -34,9 +34,9 @@ endef
 define Build/Configure
 endef
 
-define Package/$(PKG_NAME)/install
+define Package/lua-libmodbus/install
 	$(INSTALL_DIR) $(1)/usr/lib/lua
 	$(INSTALL_BIN) $(PKG_BUILD_DIR)/libmodbus.so $(1)/usr/lib/lua
 endef
 
-$(eval $(call BuildPackage,$(PKG_NAME)))
+$(eval $(call BuildPackage,lua-libmodbus))