configs: snps_archs38_vdk: use same headers as kernel

Instead of downloading a *different* version of the kernel for the
headers as for the headers itself, use the same one.
BR2_KERNEL_HEADERS_AS_KERNEL is the default, but we have to set the
custom version.

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

configs/snps_archs38_vdk_defconfig

@@ -9,7 +9,7 @@ BR2_ROOTFS_OVERLAY="board/synopsys/axs10x/fs-overlay"
 BR2_TARGET_ROOTFS_EXT2=y
 
 # Linux headers same as kernel, a 4.9 series
-BR2_KERNEL_HEADERS_4_9=y
+BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_4_9=y
 
 # Kernel
 BR2_LINUX_KERNEL=y