revert Lua patches

external/lua/lmathlib.c

@@ -4,11 +4,6 @@
 ** See Copyright Notice in lua.h
 */
 
-/***
- * Math and algorithms.
- * @module math
- */
-
 #define lmathlib_c
 #define LUA_LIB
 
@@ -651,26 +646,6 @@ static void setrandfunc (lua_State *L) {
   luaL_setfuncs(L, randfuncs, 1);
 }
 
-/***
- * Linearly interpolates using the values given.
- *
- * Returns `x + (y - x) * z`
- *
- * @function lerp
- * @tparam number x
- * @tparam number y
- * @tparam number z
- */
-static int
-math_lerp(lua_State *L)
-{
-	double x; /* parameter 1 (number) */
-
-	x = luaL_checknumber(L, 1);
-	lua_pushnumber(L, x + (luaL_checknumber(L, 2) - x) * luaL_checknumber(L, 3));
-	return 1;
-}
-
 /* }================================================================== */
 
 
@@ -740,7 +715,6 @@ static const luaL_Reg mathlib[] = {
   {"floor", math_floor},
   {"fmod",   math_fmod},
   {"ult",   math_ult},
-  {"lerp",  math_lerp},
   {"log",   math_log},
   {"max",   math_max},
   {"min",   math_min},