Add incomplet long double math support to libmingwex.a

winsup/mingw/mingwex/math/atan2f.c

@@ -0,0 +1,15 @@
+/*
+ * Written by J.T. Conklin <jtc@netbsd.org>.
+ * Public domain.
+ *
+ */
+
+#include <math.h>
+
+float
+atan2f (float y, float x)
+{
+  float res;
+  asm ("fpatan" : "=t" (res) : "u" (y), "0" (x) : "st(1)");
+  return res;
+}