tpm: Avoid qerror_report_err() outside QMP command handlers

qerror_report_err() is a transitional interface to help with
converting existing monitor commands to QMP.  It should not be used
elsewhere.  Replace by error_report_err() in initial startup helper
configure_tpm().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>

tpm.c

diff --git a/tpm.c b/tpm.c
index c371023..4ffd9b9 100644
--- a/tpm.c
+++ b/tpm.c
@@ -162,8 +162,7 @@
     /* validate backend specific opts */
     qemu_opts_validate(opts, be->opts, &local_err);
     if (local_err) {
-        qerror_report_err(local_err);
-        error_free(local_err);
+        error_report_err(local_err);
         return 1;
     }
 
@@ -174,8 +173,7 @@
 
     tpm_backend_open(drv, &local_err);
     if (local_err) {
-        qerror_report_err(local_err);
-        error_free(local_err);
+        error_report_err(local_err);
         return 1;
     }