lora32u4ii: stdout: Add pprint for PSTR (pgmspace strings)

include/arch/lora32u4ii/driver/stdout.h

 #ifndef STANDARDOUTPUT_H
 #define STANDARDOUTPUT_H
 
+#include <avr/pgmspace.h>
 #include "object/outputstream.h"
 
 class StandardOutput : public OutputStream {
@@ -12,6 +13,7 @@ class StandardOutput : public OutputStream {
 		void setup();
 
 		virtual void put(char c) override;
+		OutputStream & pprint(const char *text);
 };
 
 extern StandardOutput kout;

src/arch/lora32u4ii/driver/stdout.cc

 #include "driver/stdout.h"
 #include <avr/io.h>
-#include <avr/interrupt.h>
 
 #ifndef BAUD
 #define BAUD 9600UL
@@ -24,6 +23,17 @@ void StandardOutput::setup()
 	//UCSR1D = 0;
 }
 
+OutputStream & StandardOutput::pprint(const char *text)
+{
+	PGM_P p = reinterpret_cast<PGM_P>(text);
+	char c;
+	while ((c = pgm_read_byte(p++))) {
+		put(c);
+	}
+	return *this;
+}
+
+
 void StandardOutput::put(char c)
 {
 	while (!(UCSR1A & _BV(UDRE1)));