boards: Convert stm32l496g_disco to HWM v2

Port the board to HWMv2.

Signed-off-by: Guillaume Gautier <guillaume.gautier-ext@st.com>

boards/boards_legacy/arm/stm32l496g_disco/Kconfig.board

@@ -1,10 +0,0 @@
-# STM32L496G Discovery board configuration
-
-# Copyright (c) 2016 Open-RnD Sp. z o.o.
-# Copyright (c) 2016 BayLibre, SAS
-# Copyright (c) 2019 Centaur Analytics, Inc
-# SPDX-License-Identifier: Apache-2.0
-
-config BOARD_STM32L496G_DISCO
-	bool "STM32L496G Discovery Development Board"
-	depends on SOC_STM32L496XX

boards/st/stm32l496g_disco/Kconfig.defconfig

@@ -6,9 +6,6 @@
 
 if BOARD_STM32L496G_DISCO
 
-config BOARD
-	default "stm32l496g_disco"
-
 config SPI_STM32_INTERRUPT
 	default y
 	depends on SPI

boards/st/stm32l496g_disco/Kconfig.stm32l496g_disco

@@ -0,0 +1,5 @@
+# Copyright (c) 2019 Centaur Analytics, Inc
+# SPDX-License-Identifier: Apache-2.0
+
+config BOARD_STM32L496G_DISCO
+	select SOC_STM32L496XX

boards/st/stm32l496g_disco/board.yml

@@ -0,0 +1,5 @@
+board:
+  name: stm32l496g_disco
+  vendor: st
+  socs:
+    - name: stm32l496xx

boards/st/stm32l496g_disco/doc/index.rst

@@ -155,7 +155,7 @@ Other hardware features are not yet supported on this Zephyr port.
 
 The default configuration can be found in the defconfig file:
 
-	``boards/arm/stm32l496g_disco/stm32l496g_disco_defconfig``
+	``boards/st/stm32l496g_disco/stm32l496g_disco_defconfig``
 
 
 Connections and IOs

boards/st/stm32l496g_disco/stm32l496g_disco_defconfig

@@ -1,8 +1,5 @@
 # SPDX-License-Identifier: Apache-2.0
 
-CONFIG_SOC_SERIES_STM32L4X=y
-CONFIG_SOC_STM32L496XX=y
-
 # Enable MPU
 CONFIG_ARM_MPU=y