TAKE - fixes a couple of btree assert trips in debug kernels

[Steve Lord <lord@xxxxxxx>]

Looks like the optimizations in the btree code which went in last
week confused the compiler (or me) in a couple of cases. Back out
a few optimizations which stops the asserts from tripping.

Steve

Date:  Wed Jul 17 11:29:46 PDT 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:123164a
linux/fs/xfs/xfs_bmap_btree.c - 1.125
        - be less aggressive caching btree block contents outside the block