error: Use error_reportf_err() where it makes obvious sense

Done with this Coccinelle semantic patch

    @@
    expression FMT, E, S;
    expression list ARGS;
    @@
    -    error_report(FMT, ARGS, error_get_pretty(E));
    +    error_reportf_err(E, FMT/*@@@*/, ARGS);
    (
    -    error_free(E);
    |
	 exit(S);
    |
	 abort();
    )

followed by a replace of '%s"/*@@@*/' by '"' and some line rewrapping,
because I can't figure out how to make Coccinelle transform strings.

We now use the error whole instead of just its message obtained with
error_get_pretty().  This avoids suppressing its hint (see commit
50b7b00), but I can't see how the errors touched in this commit could
come with hints.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1450452927-8346-12-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
diff --git a/block/sheepdog.c b/block/sheepdog.c
index dd8301b..6986be8 100644
--- a/block/sheepdog.c
+++ b/block/sheepdog.c
@@ -2405,9 +2405,8 @@
 
     ret = do_sd_create(s, &new_vid, 1, &local_err);
     if (ret < 0) {
-        error_report("failed to create inode for snapshot: %s",
-                     error_get_pretty(local_err));
-        error_free(local_err);
+        error_reportf_err(local_err,
+                          "failed to create inode for snapshot: ");
         goto cleanup;
     }