switch mainboards over to use BOARD_ID_AUTO

This patch switches the mainboards with board id straps
to use BOARD_ID_AUTO instead of BOARD_ID_SUPPORT.
On urara, which does not have those straps, the option is
removed. (And re-added for urara derivatives through setting
the config option BOARD_ID_MANUAL

BRANCH=none
BUG=chrome-os-partner:37593
TEST=emerg-nyan_big coreboot, emerge-urara coreboot, emerge-buranku coreboot

Change-Id: I5ac4024c6f1f9b9d7a5179d88722c69b23b82bbd
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 22a470698f9c9ed275aa8150a5bb8d8cf368b050
Original-Signed-off-by: Stefan Reinauer <reinauer@chromium.org>
Original-Change-Id: I48c291ad6f255a28c833bebc2638bfafa2782e74
Original-Reviewed-on: https://chromium-review.googlesource.com/262935
Original-Reviewed-by: Vadim Bendebury <vbendeb@google.com>
Reviewed-on: http://review.coreboot.org/9906
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
diff --git a/src/mainboard/google/purin/Kconfig b/src/mainboard/google/purin/Kconfig
index 0d1965f..158d9d5 100644
--- a/src/mainboard/google/purin/Kconfig
+++ b/src/mainboard/google/purin/Kconfig
@@ -21,7 +21,7 @@
 
 config BOARD_SPECIFIC_OPTIONS # dummy
 	def_bool y
-	select BOARD_ID_SUPPORT
+	select BOARD_ID_AUTO
 	select BOARD_ROMSIZE_KB_2048
 	select CHROMEOS_VBNV_FLASH
 	select COMMON_CBFS_SPI_WRAPPER