hwpmc - wither ppro and p4

Intel now provides comprehensive tables for all performance counters
and the various valid configuration permutations as text .json files.
I've converted libpmc to use these and simplified the hwpmc_core to
pass the values through. I'd like to remove all the existing Intel
tables from the kernel. The one gotcha is that they don't support
pentium pro and and pentium IV.

Based on the i386 discussion I recognize that there's a great deal of
sentimental attachment to older hardware. However, there's very few
users of hwpmc on _amd64_ kernels on new hardware. I don't think
anyone is doing low level optimization on 15 year old Intel hardware.

I'm going to remove all the tables and the now unsupported p4 and ppro
configuration bits in the kmod. However, if someone feels strongly
enough to implement the corresponding tables for p4 and ppro I will
reinstate the files in to the build.

-M