mb/amd/mandolin: use SoC UART for console if LPC UART isn't present

Using the SOC's UART 0 as console requires moving a few resistors on the
Mandolin board.

BUG=b:165020060
TEST=coreboot console works on SoC UART 0 when AMD_LPC_DEBUG_CARD isn't
selected.

Change-Id: Idaf73ae84f54028da2182ce42035f9ecd63f4776
Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44528
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

src/mainboard/amd/mandolin/Kconfig

@@ -10,6 +10,7 @@ config BOARD_SPECIFIC_OPTIONS
 	select BOARD_ROMSIZE_KB_8192 if BOARD_AMD_MANDOLIN
 	select AZALIA_PLUGIN_SUPPORT
 	select HAVE_ACPI_RESUME
+	select PICASSO_CONSOLE_UART if !AMD_LPC_DEBUG_CARD
 
 config FMDFILE
 	string