security: Do not restore labels on device tree binary

A device tree binary file specified by /domain/os/dtb element is a
read-only resource similar to kernel and initrd files. We shouldn't
restore its label when destroying a domain to avoid breaking other
domains configure with the same device tree.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

src/security/security_dac.c

@@ -1128,10 +1128,6 @@ virSecurityDACRestoreAllLabel(virSecurityManagerPtr mgr,
         virSecurityDACRestoreFileLabel(priv, def->os.loader->nvram) < 0)
         rc = -1;
 
-    if (def->os.dtb &&
-        virSecurityDACRestoreFileLabel(priv, def->os.dtb) < 0)
-        rc = -1;
-
     return rc;
 }
 

src/security/security_selinux.c

@@ -2034,10 +2034,6 @@ virSecuritySELinuxRestoreAllLabel(virSecurityManagerPtr mgr,
         virSecuritySELinuxRestoreFileLabel(mgr, def->os.loader->nvram) < 0)
         rc = -1;
 
-    if (def->os.dtb &&
-        virSecuritySELinuxRestoreFileLabel(mgr, def->os.dtb) < 0)
-        rc = -1;
-
     return rc;
 }