makefs: #define Apple Partition bits

NetBSD defines these in sys/bootblock.h, which we don't have. Add local
defintions in cd9660_eltorito.c (as OpenBSD did) to reduce diffs between
the three makefs implementations.

Obtained from: OpenBSD
Sponsored by: The FreeBSD Foundation

(cherry picked from commit f0bef3d20eb6e28cf66a42c6d34fdfe80a784365)