libpayload: Separate video initialization and the video console.

It's possible to want to display text on the display without using it as a
console. This change separates the initialization of the video code from
setting up the video console by pulling out everything but installing the
console into a new function called video_init.

Change-Id: Ie07654ca13f79489c0e9b3a4998b96f598ab8513
Signed-off-by: Gabe Black <gabeblack@google.com>
Reviewed-on: http://review.coreboot.org/1733
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

payloads/libpayload/include/libpayload.h

@@ -192,6 +192,7 @@ void speaker_tone(u16 freq, unsigned int duration);
  * @ingroup input
  * @{
  */
+int video_init(void);
 int video_console_init(void);
 void video_console_putchar(unsigned int ch);
 void video_console_putc(u8 row, u8 col, unsigned int ch);