debug_dump: improved printout

- use 'h' suffix when len printed in hexa
- for missing bytes at the end (not aligned to 16 B) print 2 spaces
instead of 1, because it stands for 2 nibbles. Otherwise the ASCII
representation would be moved left (the muber of chars didn't match).

src/debug.cpp

@@ -183,7 +183,7 @@ void debug_dump(const void *lp, int len)
         char Buff[81];
         char tmpBuf[10];
 
-        _dprintf("Dump of %d=%x bytes\n", len, len);
+        _dprintf("Dump of %d=%xh bytes\n", len, len);
         start = 0L;
         while (start < len) {
                 /* start line with pointer position key */
@@ -196,7 +196,7 @@ void debug_dump(const void *lp, int len)
                                 snprintf(tmpBuf, sizeof tmpBuf, "%02X", ((int)(*p) & 0xFF));
                                 strcat(Buff, tmpBuf);
                         } else
-                                strcat(Buff, " ");
+                                strcat(Buff, "  ");
                         if (j % 2 == 1) /* space between groups of 2 */
                                 strcat(Buff, " ");
                         if (j == 7)     /* space between groups of 8 */