[ARM PATCH] 1674/1: better ARM division routines

Patch from Nicolas Pitre

Here's my rewrite of the ARM division routines:

 - take advantage of the clz instruction on ARMv5+
 - simpler and faster code for modulo routines
 - fast path for power of 2 divisors
 - other miscellaneous optimizations

This code has already been merged into gcc-3.4.