cc3200: Re-add support for UART REPL (MICROPY_STDIO_UART setting).
UART REPL support was lost in os.dupterm() refactorings, etc. As
os.dupterm() is there, implement UART REPL support at the high level -
if MICROPY_STDIO_UART is set, make default boot.py contain os.dupterm()
call for a UART. This means that changing MICROPY_STDIO_UART value will
also require erasing flash on a module to force boot.py re-creation.
diff --git a/py/misc.h b/py/misc.h
index 7584bc0..146b9a8 100644
--- a/py/misc.h
+++ b/py/misc.h
@@ -46,6 +46,10 @@
#define MAX(x, y) ((x) > (y) ? (x) : (y))
#endif
+// Classical double-indirection stringification of preprocessor macro's value
+#define _MP_STRINGIFY(x) #x
+#define MP_STRINGIFY(x) _MP_STRINGIFY(x)
+
/** memory allocation ******************************************/
// TODO make a lazy m_renew that can increase by a smaller amount than requested (but by at least 1 more element)