disk: Resolve issues with disk partition build/start checks

https://bugzilla.redhat.com/show_bug.cgi?id=1439132

Commit id 'a48c674f' added a check for format types "dvh" and "pc98"
to use the parted print processing instead of using blkid processing
in order to validate the label on the disk was what is expected for
disk pool startup. However, commit id 'a4cb4a74' really messed things
up by missing an else condition causing PARTEDFindLabel to always
return DIFFERENT.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

src/storage/storage_util.c

@@ -3245,8 +3245,8 @@ virStorageBackendPARTEDFindLabel(const char *device,
     /*  Does the on disk match what the pool desired? */
     if (STREQ(start, format))
         ret = VIR_STORAGE_PARTED_MATCH;
-
-    ret = VIR_STORAGE_PARTED_DIFFERENT;
+    else
+        ret = VIR_STORAGE_PARTED_DIFFERENT;
 
  cleanup:
     virCommandFree(cmd);