[PATCH] Miscellaneous bug and warning fixes

This patch fixes a couple of bugs revealed in new features recently
added to -mm1:
* fixes warnings due to inconsistent use of const struct inode *inode
* fixes bug that prevent a kernel from booting with audit on, and SELinux off
  due to a missing function in security/dummy.c
* fixes a bug that throws spurious audit_panic() messages due to a missing
  return just before an error_path label
* some reasonable house cleaning in audit_ipc_context(),
  audit_inode_context(), and audit_log_task_context()

Signed-off-by: Dustin Kirkland <dustin.kirkland@us.ibm.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>