Add hwpmc support for Intel Atom Goldmont microarchitecture

Recognize new micro-architecture in hwpmc_intel driver. Based on Intel
document 325462-071US. Tested with tools/test/hwpmc/pmctest.py
on Atom E3930 SoC.

Submitted by: Dawid Gorecki <dgr@semihalf.com>
Reviewed by: kib
Obtained from: Semihalf
Sponsored by: Stormshield
Differential Revision: https://reviews.freebsd.org/D24310