qemu-img: Fix convert, amend error messages for unknown options

Message quality regressed in commit dc523cd.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

qemu-img.c

@@ -1554,8 +1554,7 @@ static int img_convert(int argc, char **argv)
         if (options) {
             qemu_opts_do_parse(opts, options, NULL, &local_err);
             if (local_err) {
-                error_report("Invalid options for file format '%s'", out_fmt);
-                error_free(local_err);
+                error_report_err(local_err);
                 ret = -1;
                 goto out;
             }
@@ -3001,8 +3000,7 @@ static int img_amend(int argc, char **argv)
     if (options) {
         qemu_opts_do_parse(opts, options, NULL, &err);
         if (err) {
-            error_report("Invalid options for file format '%s'", fmt);
-            error_free(err);
+            error_report_err(err);
             ret = -1;
             goto out;
         }

tests/qemu-iotests/061.out

@@ -288,7 +288,6 @@ qemu-img: Error while amending options: Invalid argument
 Unknown compatibility level 0.42.
 qemu-img: Error while amending options: Invalid argument
 qemu-img: Invalid parameter 'foo'
-qemu-img: Invalid options for file format 'qcow2'
 Changing the cluster size is not supported.
 qemu-img: Error while amending options: Operation not supported
 Changing the encryption flag is not supported.