Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

o Rework ARMv7 events list using aliases - same way as we have for arm64.
o Extend it with Cortex A9-specific events.

Convert remaining hwpmc(4) debug printfs over to KTR to unbreak the build
for at least powerpc kernels. Missed in r282658.

MFC after: 10 days

Remove all the handcrafted assembly in hwpmc_armv7.c and use the
common (autogenerated) versions. Removes extra vertical space,
and makes it easier to grep for usage throughout the tree.
Conditionally compile only for arm6 [1] (yes sounds odd but is right).

Submitted by: andrew [1]
Reviewed by: gnn, andrew (ian earlier version I think)
Differential Revision: https://reviews.freebsd.org/D2159
Obtained from: Cambridge/L41
Sponsored by: DARPA, AFRL

The cpu_id macro was renamed in r278529, catch up with this new name.

Add ARMv7 performance monitoring counters.

Differential Revision: https://reviews.freebsd.org/D1687
Reviewed by: rpaulo
Sponsored by: DARPA, AFRL