console: Drop driver list in ramstage

This framework was only available in ramstage. So we had to define
console output functions separately for bootblock, romstage and SMM.
Follow-up patches will re-enable all the consoles removed here,
in a more flexible fashion, and with less lines-of-code and copy-paste.

Also the driver list is not in a well-defined order and some of the
loops could exit without visiting all drivers.

NOTE: This build has no console in ramstage.

Change-Id: Iaddc495aaca37e2a6c2c3f802a0dba27bf227a3e
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/5337
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>

src/drivers/uart/uart8250mem.c

@@ -116,14 +116,6 @@ unsigned char uart_rx_byte(void)
 	return uart8250_mem_rx_byte(base);
 }
 
-int uart_can_rx_byte(void)
-{
-	u32 base = uart_platform_base(0);
-	if (!base)
-		return 0;
-	return uart8250_mem_can_rx_byte(base);
-}
-
 void uart_tx_flush(void)
 {
 	u32 base = uart_platform_base(0);