fix: BSP: Port AG2 dev Flash support to AG2

* Ports the board support of the Akita Gen2 development board to the
Akita Gen2 production board.

Signed-Off-By: Alexander Preißner <alexander.preissner@blik.io>

Closes zephyrproject-rtos#25

boards/arm/akita_gen2/CMakeLists.txt

@@ -1,3 +1,8 @@
 zephyr_library()
 zephyr_library_sources(pinmux.c)
 zephyr_library_include_directories(${PROJECT_SOURCE_DIR}/drivers)
+
+zephyr_compile_definitions(
+    -DFLASH_AREA_NFFS_OFFSET=0
+    -DFLASH_AREA_NFFS_SIZE=8192
+)

boards/arm/akita_gen2/Kconfig.defconfig

@@ -66,13 +66,64 @@ config ADC_0
 
 endif # ADC
 
+
 if SPI
 
 config SPI_0
-	def_bool y
+    def_bool n
+
+config SPI_0_IRQ_PRI
+    default 10
 
 endif # SPI
 
+
+if FLASH
+	config SPI
+		def_bool y
+	config SPI_0
+		def_bool y
+	config SPI_MCUX_DSPI
+		def_bool y
+	config SPI_FLASH_W25QXXXX
+		def_bool y
+	config SPI_FLASH_W25QXXXX_SPI_NAME
+		default "SPI_0"
+	choice SPI_FLASH_W25QXXXX_DEVICE
+		default SPI_FLASH_W25QXXXX_DEVICE_W25QXXFW
+	endchoice
+	config SPI_FLASH_W25QXXXX_SPI_FREQ_0
+		default 500000
+	config SPI_FLASH_W25QXXXX_SPI_SLAVE
+		default 0
+
+endif # FLASH
+
+
+if FILE_SYSTEM_NFFS
+
+	config FS_NFFS_FLASH_DEV_NAME
+		default "W25QXXXX"
+	config FS_NFFS_NUM_INODES
+		default 100
+	config FS_NFFS_NUM_BLOCKS
+		default 100
+	config FS_NFFS_NUM_FILES
+		default 4
+	config FS_NFFS_NUM_DIRS
+		default 4
+	config FS_NFFS_NUM_CACHE_INODES
+		default 1
+	config FS_NFFS_NUM_CACHE_BLOCKS
+		default 1
+	config NFFS_FILESYSTEM_MAX_AREAS
+		default 8
+	config NFFS_FILESYSTEM_MAX_BLOCK_SIZE
+		default 256
+
+endif # FILE_SYSTEM_NFFS
+
+
 if LIS3DH
 
 config LIS3DH_GPIO_NAME