alsa-utils: fix packaging

alsa-utils: fix packaging

In the previous refactoring of this package[1] I forgot to add provides
when merging some packages, which meant that installation of alsa-utils
wouldn't succeed:

  - nothing provides alsa-utils-aplaymidi needed by alsa-utils-1.2.15.1-r0.cortexa57 from oe-repo
  - nothing provides alsa-utils-aplaymidi2 needed by alsa-utils-1.2.15.1-r0.cortexa57 from oe-repo
  - nothing provides alsa-utils-arecordmidi needed by alsa-utils-1.2.15.1-r0.cortexa57 from oe-repo
  - nothing provides alsa-utils-arecordmidi2 needed by alsa-utils-1.2.15.1-r0.cortexa57 from oe-repo
  - nothing provides alsa-utils-axfer needed by alsa-utils-1.2.15.1-r0.cortexa57 from oe-repo

This is because the auto-splitting generates a package for each of the
binaries, but there are explicit FILES that take priority which result
in the binaries being in another package.  However, the dependencies
still exist. We could filter the package list after the split, but it is
easier to add RPROVIDES for arecord and a*midi to the relevant packages,
so that the dependencies are satisfied.

Also axfer is a separate tool, so put that in its own package instead of
merging with aplay.

Finally, add a PR, as it appears that dynamically-generated packaging
isn't enough to change the hash, and the wrong packages were being pulled
from sstate.

Signed-off-by: Ross Burton <ross.burton@arm.com>
Tested-by: Ryan Eatmon <reatmon@ti.com>
Signed-off-by: Antonin Godard <antonin.godard@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>