target-s390: Add facilities bits and sets

Name the facilities bits, collect the set of bits for tcg and the various
real processor revisions.  Update the set of facilities reported for TCG.

Signed-off-by: Richard Henderson <rth@twiddle.net>
target-s390: Raise OPERATION exception for disabled insns

Signed-off-by: Richard Henderson <rth@twiddle.net>
target-s390: Implement SAM31 and SAM64

Signed-off-by: Richard Henderson <rth@twiddle.net>
target-s390: Implement EPSW

Signed-off-by: Richard Henderson <rth@twiddle.net>
target-s390: Fix STIDP

The implementation had been incomplete, as we did not store the
machine type.

Signed-off-by: Richard Henderson <rth@twiddle.net>
target-s390: Fix STURA

We were storing 16 bits instead of 32.

Signed-off-by: Richard Henderson <rth@twiddle.net>
target-s390: Implement LURA, LURAG, STURG

Signed-off-by: Richard Henderson <rth@twiddle.net>
target-s390: Implement ECAG

Signed-off-by: Richard Henderson <rth@twiddle.net>