[releng] Add a little debugging when pkg_exists fails

[Till Maas]

commit 5c22d5b1a3412ba58c70d3f6aa6fc2cac5ce8e95
Author: Pierre-Yves Chibon <pingou at pingoured.fr>
Date:   Mon Nov 3 17:50:02 2014 +0100

    Add a little debugging when pkg_exists fails

 scripts/process-git-requests/process-git-requests |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/scripts/process-git-requests/process-git-requests b/scripts/process-git-requests/process-git-requests
index f308cd6..46e069e 100755
--- a/scripts/process-git-requests/process-git-requests
+++ b/scripts/process-git-requests/process-git-requests
@@ -156,7 +156,8 @@ def add_package(pkgdb, request, bug):
     def pkg_exists(pkg):
         try:
             pkgdb.get_package(str(pkg))
-        except PkgDBException:
+        except PkgDBException as err:
+            log.debug('Error when retrieving package %s: %s', str(pkg), err)
             # We get an error back if (at least) the package doesn't exist.
             return False
         return True