In lieu of Michael Holzt, add his serbb serial bit-bang code so it

will be available in the upcoming avrdude release.

His addition has been implemented by means of a generalized bit-bang
interface that contains the common part between serial and paralle
bit-bang devices, and specialed backends for the serial and parallel
port connections.


git-svn-id: svn://svn.savannah.nongnu.org/avrdude/trunk@515 81a1dc3b-b13d-400b-aceb-764788c761c2

avrdude/pgm.h

@@ -83,6 +83,7 @@ typedef struct programmer_t {
   int  (*set_sck_period) (struct programmer_t * pgm, double v);
   char config_file[PATH_MAX]; /* config file where defined */
   int  lineno;                /* config file line number */
+  char flag;		      /* for private use of the programmer */
 } PROGRAMMER;