micropython: add micropython component

components/language/micropython/lib/libm_dbl/tanh.c

@@ -0,0 +1,12 @@
+#include <math.h>
+
+double tanh(double x) {
+    int sign = 0;
+    if (x < 0) {
+        sign = 1;
+        x = -x;
+    }
+    x = expm1(-2 * x);
+    x = x / (x + 2);
+    return sign ? x : -x;
+}