x86: Annotate undefined opcodes
x86: Annotate undefined opcodes

Signed-off-by: Pekka Enberg <add4fcd06328a394f0ad91feda7ee057316dc5ed@iki.fi>

libcpu/libcpu,libcpu/libcpu,curtiszimmerman/libcpu,monocasa/libcpu,curtiszimmerman/libcpu,libcpu/libcpu,monocasa/libcpu,curtiszimmerman/libcpu,curtiszimmerman/libcpu,monocasa/libcpu,monocasa/libcpu,libcpu/libcpu