x86/emul: Add structure names to opcode tables

x86/emul: Add structure names to opcode tables

No functional change, but it makes the diff context line more helpful when
reviewing patches which alter the opcode tables.  e.g. Consider:

  --- a/xen/arch/x86/x86_emulate/x86_emulate.c
  +++ b/xen/arch/x86/x86_emulate/x86_emulate.c
  @@ -370,7 +370,7 @@ static const struct {
       [0x0c ... 0x0f] = { .simd_size = simd_packed_fp },
       [0x10] = { .simd_size = simd_packed_int },
       [0x13] = { .simd_size = simd_other, .two_op = 1 },
  -    [0x14 ... 0x15] = { .simd_size = simd_packed_fp },
  +    [0x14 ... 0x16] = { .simd_size = simd_packed_fp },
       [0x17] = { .simd_size = simd_packed_int, .two_op = 1 },
       [0x18 ... 0x19] = { .simd_size = simd_scalar_fp, .two_op = 1 },
       [0x1a] = { .simd_size = simd_128, .two_op = 1 },

which is entirely ambiguous between 0f38 and 0f3a, and the same diff with this
change in place:

  --- a/xen/arch/x86/x86_emulate/x86_emulate.c
  +++ b/xen/arch/x86/x86_emulate/x86_emulate.c
  @@ -370,7 +370,7 @@ static const struct ext0f38_table {
       [0x0c ... 0x0f] = { .simd_size = simd_packed_fp },
       [0x10] = { .simd_size = simd_packed_int },
       [0x13] = { .simd_size = simd_other, .two_op = 1 },
  -    [0x14 ... 0x15] = { .simd_size = simd_packed_fp },
  +    [0x14 ... 0x16] = { .simd_size = simd_packed_fp },
       [0x17] = { .simd_size = simd_packed_int, .two_op = 1 },
       [0x18 ... 0x19] = { .simd_size = simd_scalar_fp, .two_op = 1 },
       [0x1a] = { .simd_size = simd_128, .two_op = 1 },

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>