[openwrt/openwrt] image: improve Kconfig for seperate ramdisk option

[LEDE Commits]

dangole pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/dc68af4a1312775f3aeade7c46786858725cfabe

commit dc68af4a1312775f3aeade7c46786858725cfabe
Author: Daniel Golle <daniel at makrotopia.org>
AuthorDate: Thu Feb 25 14:13:50 2021 +0000

    image: improve Kconfig for seperate ramdisk option
    
    * show only if target supports it (ie. seperate_ramdisk feature set)
    * select XZ compression by default of ramdisk is seperate
    
    Signed-off-by: Daniel Golle <daniel at makrotopia.org>
---
 config/Config-images.in | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/config/Config-images.in b/config/Config-images.in
index 080fee2cce..b1f5b43719 100644
--- a/config/Config-images.in
+++ b/config/Config-images.in
@@ -17,6 +17,7 @@ menu "Target Images"
 			default TARGET_INITRAMFS_COMPRESSION_LZMA if TARGET_lantiq
 			default TARGET_INITRAMFS_COMPRESSION_LZMA if TARGET_mpc85xx
 			default TARGET_INITRAMFS_COMPRESSION_LZMA if TARGET_ramips
+			default TARGET_INITRAMFS_COMPRESSION_XZ if USES_SEPERATE_INITRAMFS
 			default TARGET_INITRAMFS_COMPRESSION_NONE
 			depends on TARGET_ROOTFS_INITRAMFS
 			help
@@ -66,7 +67,7 @@ menu "Target Images"
 
 		config TARGET_ROOTFS_INITRAMFS_SEPERATE
 			bool "seperate ramdisk"
-			depends on TARGET_ROOTFS_INITRAMFS && !TARGET_INITRAMFS_FORCE
+			depends on USES_SEPERATE_INITRAMFS && TARGET_ROOTFS_INITRAMFS && !TARGET_INITRAMFS_FORCE
 			default y if USES_SEPERATE_INITRAMFS
 			help
 			  Generate seperate initrd.cpio instead of embedding it.