TAKE - fix super block reference leak

[Steve Lord <lord@sgi.com>]

Was not harmful in normal operation, but caused a memory leak at unmount
and oopses if you unload and reload xfs as a module

Date:  Wed Mar  6 04:40:51 PST 2002
Workarea:  jen.americas.sgi.com:/src/lord/xfs-linux.2.4

The following file(s) were checked into:
  bonnie.engr.sgi.com:/isms/slinx/2.4.x-xfs


Modid:  2.4.x-xfs:slinx:113384a
linux/fs/xfs/xfs_buf.h - 1.82
	- No longer treat the super block specially in the delayed write queue

linux/fs/xfs/xfs_mount.c - 1.273
	- Fix a reference leak on the super block buffer - causes a small memory
	  leak under pressure, and can cause oopses if loading and unloading an
	  xfs module.

linux/fs/xfs/pagebuf/page_buf.c - 1.12
	- No longer treat the super block specially in the delayed write queue