ARM: tegra: remove custom define for Jetson TK1

Now that Kconfig has a per-board option, we can use that directly rather
than inventing a custom define for the AS3722 code to determine which
board it's being built for.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/board/nvidia/venice2/as3722_init.h b/board/nvidia/venice2/as3722_init.h
index a7b2403..06c366e 100644
--- a/board/nvidia/venice2/as3722_init.h
+++ b/board/nvidia/venice2/as3722_init.h
@@ -18,7 +18,7 @@
 #define AS3722_LDO6VOLTAGE_REG	0x16	/* VDD_SDMMC */
 #define AS3722_LDCONTROL_REG	0x4E
 
-#ifdef CONFIG_BOARD_JETSON_TK1
+#ifdef CONFIG_TARGET_JETSON_TK1
 #define AS3722_SD0VOLTAGE_DATA	(0x3C00 | AS3722_SD0VOLTAGE_REG)
 #else
 #define AS3722_SD0VOLTAGE_DATA	(0x2800 | AS3722_SD0VOLTAGE_REG)
diff --git a/configs/jetson-tk1_defconfig b/configs/jetson-tk1_defconfig
index 9ce97c9..6926257 100644
--- a/configs/jetson-tk1_defconfig
+++ b/configs/jetson-tk1_defconfig
@@ -1,4 +1,3 @@
 CONFIG_SPL=y
-CONFIG_SYS_EXTRA_OPTIONS="BOARD_JETSON_TK1="
 +S:CONFIG_ARM=y
 +S:CONFIG_TARGET_JETSON_TK1=y