Add Error to Software Version Interface

This commit adds a InvalidSignature error to the
Software Version interface. It will ensure that
if the error is hit during the verificatioon of
an image, a corresponding error is available to the
user.

Signed-off-by: Zami Seck <zimzam17@gmail.com>
Change-Id: Iba2eb7689a3e34db15e4a5d31accb69c18f906f5
diff --git a/yaml/xyz/openbmc_project/Software/Version.errors.yaml b/yaml/xyz/openbmc_project/Software/Version.errors.yaml
index e62ee4b..9840b30 100644
--- a/yaml/xyz/openbmc_project/Software/Version.errors.yaml
+++ b/yaml/xyz/openbmc_project/Software/Version.errors.yaml
@@ -8,3 +8,6 @@
 - name: AlreadyExists
   description: >
     This image version already exists on the device
+- name: InvalidSignature
+  description: >
+    Signature Validation failed for image version.