configs/qemu_riscv64_virt_defconfig: bump Linux version

Since riscv64 works with linux default defconfig, this patch drop custom config.

Signed-off-by: Gwenhael Goavec-Merou <gwenhael.goavec-merou@trabucayre.com>
Tested-by: Mark Corbin <mark.corbin@embecosm.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

board/qemu/riscv64-virt/linux.config

@@ -1,23 +0,0 @@
-CONFIG_ARCH_RV64I=y
-CONFIG_SMP=y
-CONFIG_NR_CPUS=8
-CONFIG_PCI=y
-CONFIG_SYSVIPC=y
-CONFIG_NET=y
-CONFIG_PACKET=y
-CONFIG_UNIX=y
-CONFIG_INET=y
-# CONFIG_WIRELESS is not set
-CONFIG_VIRTIO_BLK=y
-CONFIG_NETDEVICES=y
-CONFIG_VIRTIO_NET=y
-# CONFIG_ETHERNET is not set
-# CONFIG_WLAN is not set
-CONFIG_SERIAL_8250=y
-CONFIG_SERIAL_8250_CONSOLE=y
-CONFIG_SERIAL_OF_PLATFORM=y
-CONFIG_VIRT_DRIVERS=y
-CONFIG_VIRTIO_MMIO=y
-CONFIG_EXT2_FS=y
-CONFIG_EXT4_FS=y
-CONFIG_TMPFS=y

configs/qemu_riscv64_virt_defconfig

@@ -10,16 +10,15 @@ BR2_TARGET_ROOTFS_EXT2=y
 BR2_TARGET_GENERIC_GETTY=y
 BR2_TARGET_GENERIC_GETTY_PORT="ttyS0"
 
-# Linux headers same as kernel, a 4.15 series
-BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_4_15=y
+# Linux headers same as kernel, a 4.20 series
+BR2_KERNEL_HEADERS_4_20=y
 
 # Kernel
 BR2_LINUX_KERNEL=y
 BR2_LINUX_KERNEL_CUSTOM_GIT=y
 BR2_LINUX_KERNEL_CUSTOM_REPO_URL="https://github.com/riscv/riscv-linux.git"
-BR2_LINUX_KERNEL_CUSTOM_REPO_VERSION="fe92d7905c6ea0ebeabeb725b8040754ede7c220"
-BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG=y
-BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="board/qemu/riscv64-virt/linux.config"
+BR2_LINUX_KERNEL_CUSTOM_REPO_VERSION="8fe28cb58bcb235034b64cbbb7550a8a43fd88be"
+BR2_LINUX_KERNEL_USE_ARCH_DEFAULT_CONFIG=y
 
 # Bootloader
 BR2_TARGET_RISCV_PK=y