info: fix mismatched format args and wrong symbol name

Bug: 416589884
Change-Id: Icbaade585932f0cbb51367e07925ef606f089697
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/482762
Commit-Queue: Scott Lee <ddoman@google.com>
Reviewed-by: Mike Frysinger <vapier@google.com>
Lint: Scott Lee <ddoman@google.com>
Tested-by: Scott Lee <ddoman@google.com>
diff --git a/git_superproject.py b/git_superproject.py
index 687429e..d808bb0 100644
--- a/git_superproject.py
+++ b/git_superproject.py
@@ -147,7 +147,8 @@
                 "git rev-parse call failed, command: git {}, "
                 "return code: {}, stderr: {}",
                 cmd,
-                p.stdwerr,
+                retval,
+                p.stderr,
             )
             return None
         return p.stdout