Merge b1_5 from b1_4 (20061213_1244)

Quiet compiler warnings from -Wundef in libsysio.
Some fixes to allow building/insmod on 2.4 kernels:
 - do_div() and other 64-bit divisions
 - bit_spin_lock usage in lock_bitlock(), et. al.
More fixes for bug 10991 (removal of ENOLCK).
Fix test 77c from bug 11238.
Add mxlnd support.
Kernel patch updates.
ldiskfs patch updates.
Remove duplicate test_56 in sanity.sh, renumbering to avoid conflicts.
Allow acceptance-small.sh to run without any reformats.