Convert CONFIG_LSCHLV2 to Kconfig et al

This converts the following to Kconfig:
   CONFIG_LSCHLV2
   CONFIG_LSXHL

Cc: Michael Walle <michael@walle.cc>
Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Michael Walle <michael@walle.cc>
diff --git a/board/buffalo/lsxl/Kconfig b/board/buffalo/lsxl/Kconfig
index ef78896..fd8f054 100644
--- a/board/buffalo/lsxl/Kconfig
+++ b/board/buffalo/lsxl/Kconfig
@@ -9,4 +9,15 @@
 config SYS_CONFIG_NAME
 	default "lsxl"
 
+choice
+	prompt "Board model"
+
+config LSCHLV2
+	bool "LSCHLV2 support"
+
+config LSXHL
+	bool "LSXHL support"
+
+endchoice
+
 endif
diff --git a/configs/lschlv2_defconfig b/configs/lschlv2_defconfig
index 0cfa6d0..8ec6ca2 100644
--- a/configs/lschlv2_defconfig
+++ b/configs/lschlv2_defconfig
@@ -7,6 +7,7 @@
 CONFIG_SYS_TEXT_BASE=0x600000
 CONFIG_NR_DRAM_BANKS=2
 CONFIG_TARGET_LSXL=y
+CONFIG_LSCHLV2=y
 CONFIG_ENV_SIZE=0x10000
 CONFIG_ENV_OFFSET=0x70000
 CONFIG_ENV_SECT_SIZE=0x10000
@@ -15,7 +16,6 @@
 CONFIG_DISTRO_DEFAULTS=y
 CONFIG_SYS_LOAD_ADDR=0x800000
 CONFIG_API=y
-CONFIG_SYS_EXTRA_OPTIONS="LSCHLV2"
 CONFIG_SHOW_BOOT_PROGRESS=y
 CONFIG_BOOTDELAY=3
 CONFIG_USE_BOOTARGS=y
diff --git a/configs/lsxhl_defconfig b/configs/lsxhl_defconfig
index 046db90..0de6fc5 100644
--- a/configs/lsxhl_defconfig
+++ b/configs/lsxhl_defconfig
@@ -7,6 +7,7 @@
 CONFIG_SYS_TEXT_BASE=0x600000
 CONFIG_NR_DRAM_BANKS=2
 CONFIG_TARGET_LSXL=y
+CONFIG_LSXHL=y
 CONFIG_ENV_SIZE=0x10000
 CONFIG_ENV_OFFSET=0x70000
 CONFIG_ENV_SECT_SIZE=0x10000
@@ -15,7 +16,6 @@
 CONFIG_DISTRO_DEFAULTS=y
 CONFIG_SYS_LOAD_ADDR=0x800000
 CONFIG_API=y
-CONFIG_SYS_EXTRA_OPTIONS="LSXHL"
 CONFIG_SHOW_BOOT_PROGRESS=y
 CONFIG_BOOTDELAY=3
 CONFIG_USE_BOOTARGS=y