Fixed #8901 -- Corrected the PostgreSQL sequence reset code when field...

Fixed #8901 -- Corrected the PostgreSQL sequence reset code when field identifiers exceed the maximum identifier length. Thanks to adam@zuerchertech.com for the report, and Matt Hoskins for the patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@13328 bcc190cf-cafb-0310-a4f2-bffc1f526a37