Add incomplet long double math support to libmingwex.a

winsup/mingw/mingwex/math/fmaxl.c

@@ -0,0 +1,7 @@
+#include <math.h>
+
+long double
+fmaxl (long double _x, long double  _y)
+{
+  return (( isgreaterequal(_x, _y) || __isnanl (_y)) ?  _x : _y );
+}