package/qemu: add zstd support

Add optional zstd compression type support for QEMU.

In order to a file compressed with zstd on host to be applied to
target QEMU, zstd on both host and target should be enabled.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Reviewed-by: Romain Naour <romain.naour@smile.fr>
Signed-off-by: Julien Olivain <ju.o@free.fr>

package/qemu/qemu.mk

@@ -271,6 +271,13 @@ else
 QEMU_OPTS += --disable-install-blobs
 endif
 
+ifeq ($(BR2_PACKAGE_ZSTD),y)
+QEMU_OPTS += --enable-zstd
+QEMU_DEPENDENCIES += zstd
+else
+QEMU_OPTS += --disable-zstd
+endif
+
 # Override CPP, as it expects to be able to call it like it'd
 # call the compiler.
 define QEMU_CONFIGURE_CMDS
@@ -460,6 +467,13 @@ else
 HOST_QEMU_OPTS += --disable-libusb
 endif
 
+ifeq ($(BR2_PACKAGE_HOST_ZSTD),y)
+HOST_QEMU_OPTS += --enable-zstd
+HOST_QEMU_DEPENDENCIES += host-zstd
+else
+HOST_QEMU_OPTS += --disable-zstd
+endif
+
 # Override CPP, as it expects to be able to call it like it'd
 # call the compiler.
 define HOST_QEMU_CONFIGURE_CMDS