base/kernel: Support zstd-compressed squashfs and cpio initramfs

Enable zstd PACKAGECONFIG knob for squashfs-tools and add support for zstd
compressed initramfs and squashfs.

(From OE-Core rev: fa146049eec5f9730781830270cc9dc55a2146f7)

Signed-off-by: Zoltán Böszörményi <zboszor@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/base.bbclass

@@ -631,6 +631,10 @@ python () {
         if path.endswith('.lz4'):
             d.appendVarFlag('do_unpack', 'depends', ' lz4-native:do_populate_sysroot')
 
+        # *.zst should DEPEND on zstd-native for unpacking
+        elif path.endswith('.zst'):
+            d.appendVarFlag('do_unpack', 'depends', ' zstd-native:do_populate_sysroot')
+
         # *.lz should DEPEND on lzip-native for unpacking
         elif path.endswith('.lz'):
             d.appendVarFlag('do_unpack', 'depends', ' lzip-native:do_populate_sysroot')