Fix compiling issue of MSVC

src/biome.cpp

@@ -23,7 +23,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "log.h"
 #include "util/numeric.h"
 #include "main.h"
-
+#include "util/mathconstants.h"
 
 NoiseParams nparams_biome_def_heat =
 	{50, 50, v3f(500.0, 500.0, 500.0), 5349, 3, 0.70};