IO Firmware: Reduce unnecessary buffer space

src/modules/px4iofirmware/mixer.cpp

@@ -418,7 +418,7 @@ mixer_callback(uintptr_t handle,
  * not loaded faithfully.
  */
 
-static char mixer_text[256];		/* large enough for one mixer */
+static char mixer_text[200];		/* large enough for one mixer */
 static unsigned mixer_text_length = 0;
 
 int

src/modules/px4iofirmware/px4io.c

@@ -82,7 +82,7 @@ static volatile uint8_t msg_next_out, msg_next_in;
  * for mixer handling. Do not allocate more than 80 bytes for
  * output.
  */
-#define NUM_MSG 2
+#define NUM_MSG 1
 static char msg[NUM_MSG][40];
 
 static void heartbeat_blink(void);