Remove some leftovers from OMAP3 support.
Set up default shstrtab entries at shstrtab initialization

Instead of waiting until the addition of the first non-default entry.
This fixes a segfault when strip(1) is asked to remove every section from
an object file.

Upstream elftoolchain ticket 463

Reviewed by:	imp
Sponsored by:	The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D1341
Add AArch64 machine time and relocations for readelf

Reviewed by:	andrew
Sponsored by:	The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D1333
Standardise on illumos for #ifdef's in zvol.c

Also correct as per style(9) on the use of #ifdef comments.

This is a no-op change as pre-cursor to a full cleanup and merge with
upstream zvol changes.

Sponsored by:	Multiplay