target/arm: Relax ordered/atomic alignment checks for LSE2

target/arm: Relax ordered/atomic alignment checks for LSE2

FEAT_LSE2 only requires that atomic operations not cross a
16-byte boundary.  Ordered operations may be completely
unaligned if SCTLR.nAA is set.

Because this alignment check is so special, do it by hand.
Make sure not to keep TCG temps live across the branch.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230530191438.411344-17-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>