rc: Make devmatch use load_kld

[des]

Summary

The default behavior of load_kld is now robust enough for devmatch.
Switching means settings from /etc/sysctl.kld.d are now properly applied
when the corresponding modules are loaded by devmatch.

While here, reduce the amount of output produced by devmatch from one
line per module to a single line.

MFC after: 1 week

[imp]

Might be good to mention, at least here, what the revs were that made load_kld work here.

[des]

In D57707#1322913, @imp wrote:

Might be good to mention, at least here, what the revs were that made load_kld work here.

The parent revision, D57706.

[imp]

In D57707#1323013, @des wrote:

In D57707#1322913, @imp wrote:

Might be good to mention, at least here, what the revs were that made load_kld work here.

The parent revision, D57706.

Ah! That's why I couldn't remember when! I've looked at it and agree!