[coreboot-gerrit] Patch merged into coreboot/master: Kconfig: Fix CONFIG_GDB_STUB dependencies

the following patch was just integrated into master:
commit 3747ba16c7ed0d47549f42848784dc3840333c7e
Author: Denis 'GNUtoo' Carikli 
Date:   Thu Dec 10 22:04:56 2015 +0100

Kconfig: Fix CONFIG_GDB_STUB dependencies

If we select CONFIG_GDB_STUB without CONFIG_SERIAL:

build/console/console.romstage.o: In function `__gdb_hw_init':
    [...]src/include/console/uart.h:74: undefined reference to `uart_init'
    build/console/console.romstage.o: In function `__gdb_tx_byte':
    [...]/src/include/console/uart.h:75: undefined reference to `uart_tx_byte'
    build/console/console.romstage.o: In function `__gdb_tx_flush':
    [...]/src/include/console/uart.h:76: undefined reference to `uart_tx_flush'
    build/console/console.romstage.o: In function `__gdb_rx_byte':
    [...]/src/include/console/uart.h:77: undefined reference to `uart_rx_byte'

Note that CONFIG_GDB_STUB should also work trough usbdebug,
    But due to the lack of testing, it has been disabled when added.
    This commit gives more information on the issue:
    f2f7f03 console: Add console for GDB

Change-Id: I9accf8189dfd2c4ae379c03649d2e5863183457b
    Signed-off-by: Denis 'GNUtoo' Carikli 
    Reviewed-on: https://review.coreboot.org/12708
    Tested-by: build bot (Jenkins)
    Reviewed-by: Martin Roth

See https://review.coreboot.org/12708 for details.

-gerrit