The only valid (embedded or explicit) prefix being the data size one
(which is a fairly common pattern), avoid going through prefix_table[].
Instead extend the "required prefix" logic to also handle PREFIX_DATA
alone in a table entry, now used to identify this case. This requires
moving the (adjusted) ->prefix_requirement logic ahead of the printing
of stray prefixes, as the latter needs to observe the new setting of
PREFIX_DATA in used_prefixes.
Also add PREFIX_OPCODE on related entries when previously there was
mistakenly no decode step through prefix_table[].
Break i386-dis-evex.h into small files such that each file is included
just once.
* i386-dis-evex.h: Break into ...
* i386-dis-evex-len.h: New file.
* i386-dis-evex-mod.h: Likewise.
* i386-dis-evex-prefix.h: Likewise.
* i386-dis-evex-reg.h: Likewise.
* i386-dis-evex-w.h: Likewise.
* i386-dis.c: Include i386-dis-evex-reg.h, i386-dis-evex-prefix.h,
i386-dis-evex.h, i386-dis-evex-len.h, i386-dis-evex-w.h and
i386-dis-evex-mod.h.
