stmhal: Enable "all special methods" configuration option.

stmhal/mpconfigport.h

@@ -63,6 +63,7 @@
 #define MICROPY_PY_BUILTINS_MEMORYVIEW (1)
 #define MICROPY_PY_BUILTINS_FROZENSET (1)
 #define MICROPY_PY_BUILTINS_EXECFILE (1)
+#define MICROPY_PY_ALL_SPECIAL_METHODS (1)
 #define MICROPY_PY_MICROPYTHON_MEM_INFO (1)
 #define MICROPY_PY_ARRAY_SLICE_ASSIGN (1)
 #define MICROPY_PY_BUILTINS_SLICE_ATTRS (1)