[OE-core] [PATCH] image-vm: Exclude DISK_SIGNATURE_GENERATED from task signature

[Richard Purdie]

Otherwise the task hash changes between server and worker context
leading to changing task checksums.  

Signed-off-by: Richard Purdie <richard.purdie at linuxfoundation.org>

diff --git a/meta/classes/image-vm.bbclass b/meta/classes/image-vm.bbclass
index 326dc04..2cd2640 100644
--- a/meta/classes/image-vm.bbclass
+++ b/meta/classes/image-vm.bbclass
@@ -46,6 +46,7 @@ BOOTDD_VOLUME_ID   ?= "boot"
 BOOTDD_EXTRA_SPACE ?= "16384"
 
 DISK_SIGNATURE ?= "${DISK_SIGNATURE_GENERATED}"
+DISK_SIGNATURE[vardepsexclude] = "DISK_SIGNATURE_GENERATED"
 
 build_boot_dd() {
 	HDDDIR="${S}/hdd/boot"