bblayers.conf: deactivate meta-musl by default
bblayers.conf: deactivate meta-musl by default

A musl distro config could reenable it again, but default it to off.

Change-Id: I84df1a8329fed3332c9bd86fc4c8de180017b40a
Signed-off-by: Koen Kooi <42e3d96910f922bdd7dd1805fe3f8aff634f391d@dominion.thruhere.net>

Angstrom-distribution/angstrom-manifest