configs/warp7: bump Kernel and U-Boot version

Bump U-Boot to 2020.07 and kernel to version 5.7.8

Signed-off-by: Pierre-Jean Texier <pjtexier@koncepto.io>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

configs/warp7_defconfig

@@ -15,7 +15,7 @@ BR2_ROOTFS_OVERLAY="board/warp7/rootfs_overlay"
 # Kernel
 BR2_LINUX_KERNEL=y
 BR2_LINUX_KERNEL_CUSTOM_VERSION=y
-BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="5.7.1"
+BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="5.7.8"
 BR2_LINUX_KERNEL_DEFCONFIG="imx_v6_v7"
 BR2_LINUX_KERNEL_DTS_SUPPORT=y
 BR2_LINUX_KERNEL_INTREE_DTS_NAME="imx7s-warp"
@@ -25,7 +25,7 @@ BR2_LINUX_KERNEL_NEEDS_HOST_OPENSSL=y
 BR2_TARGET_UBOOT=y
 BR2_TARGET_UBOOT_BOARDNAME="warp7"
 BR2_TARGET_UBOOT_CUSTOM_VERSION=y
-BR2_TARGET_UBOOT_CUSTOM_VERSION_VALUE="2020.04"
+BR2_TARGET_UBOOT_CUSTOM_VERSION_VALUE="2020.07"
 BR2_TARGET_UBOOT_FORMAT_DTB_IMX=y
 
 # wifi firmware for brcm43430