libbsd: bump to version 0.9.1

libbsd: bump to version 0.9.1

Drop upstream patches.

Add a patch fixing build with musl libc.

Update the list of licenses based on the content of COPYING. The
BSD-5-Clause license is not listed by SPDX, but that is its name in the
COPYING file.

Update the license file hash: new licenses, dates update, reformat.

Cc: Yann E. MORIN <yann.morin.1998@free.fr>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>