edit lua_api_version.h instead of autogenerating it

This will help those who do not use ccache :-)

src/gui/lua/Makefile.am

@@ -40,18 +40,3 @@ libneutrino_gui_lua_a_SOURCES = \
 	lua_threads_functions.cpp \
 	lua_video.cpp
 
-# the continuous changes of LUA_API_VERSION_* in luainstance.h
-# are not only of questionable usefulness, but they also cause
-# rebuilds all over the place, even though it is only used in
-# 2(!) source files. So split out those two definitions into an
-# autogenerated separate file, they are #if 0'ed in luainstance.h
-# already and the rest is dealt with via ccache...
-BUILT_SOURCES = lua_api_version.h
-lua_api_version.h: luainstance.h
-	@rm -f $@
-	grep '^#define.*LUA_API' $(srcdir)/luainstance.h > $@
-
-noinst_HEADERS = lua_api_version.h
-
-# so that lua_api_version.h can be found...
-AM_CPPFLAGS += -I$(builddir)

src/gui/lua/lua_api_version.h

@@ -0,0 +1,7 @@
+/*
+ * this is only used in two code files, so put it into its own
+ * header to reduce complete neutrino rebuilding all the time due
+ * to luainstance.h changes
+ */
+#define LUA_API_VERSION_MAJOR 1
+#define LUA_API_VERSION_MINOR 37

src/gui/lua/luainstance.h

@@ -30,11 +30,6 @@ extern "C" {
 
 #include "luainstance_helpers.h"
 
-#if 0
-#define LUA_API_VERSION_MAJOR 1
-#define LUA_API_VERSION_MINOR 37
-#endif
-
 void LuaInstRegisterFunctions(lua_State *L, bool fromThreads=false);
 
 /* inspired by Steve Kemp http://www.steve.org.uk/ */