configs/microchip_sama7g5ek_mmc_dev_defconfig: set custom linux version to 5.15.21 and add host openssl for linux

Fixes:
https://gitlab.com/ymorin/buildroot/-/jobs/2035821100

Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
Tested-by: Eugen Hristev <eugen.hristev@microchip.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

configs/microchip_sama7g5ek_mmc_dev_defconfig

@@ -1,6 +1,7 @@
 BR2_arm=y
 BR2_cortex_a7=y
 BR2_ARM_FPU_NEON_VFPV4=y
+BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_5_15=y
 BR2_TOOLCHAIN_BUILDROOT_WCHAR=y
 BR2_PTHREAD_DEBUG=y
 BR2_TOOLCHAIN_BUILDROOT_CXX=y
@@ -8,9 +9,12 @@ BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_EUDEV=y
 BR2_ROOTFS_POST_IMAGE_SCRIPT="support/scripts/genimage.sh"
 BR2_ROOTFS_POST_SCRIPT_ARGS="-c board/microchip/sama7g5ek/genimage.cfg"
 BR2_LINUX_KERNEL=y
+BR2_LINUX_KERNEL_CUSTOM_VERSION=y
+BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="5.15.21"
 BR2_LINUX_KERNEL_DEFCONFIG="sama7"
 BR2_LINUX_KERNEL_DTS_SUPPORT=y
 BR2_LINUX_KERNEL_INTREE_DTS_NAME="at91-sama7g5ek"
+BR2_LINUX_KERNEL_NEEDS_HOST_OPENSSL=y
 BR2_PACKAGE_LINUX_TOOLS_IIO=y
 BR2_PACKAGE_BZIP2=y
 BR2_PACKAGE_XZ=y