Remove superfluous '\n' around error_report()

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
diff --git a/exec.c b/exec.c
index 6a5adab..b44a33c 100644
--- a/exec.c
+++ b/exec.c
@@ -1188,7 +1188,7 @@
 
 error:
     if (mem_prealloc) {
-        error_report("%s\n", error_get_pretty(*errp));
+        error_report("%s", error_get_pretty(*errp));
         exit(1);
     }
     return NULL;