linux-user/s390x: Expand target_elf_gregset_t

Make use of the fact that target_elf_gregset_t is a proper structure.
This lets us drop the ugly cast to uint32_t* in the middle.

Drop ELF_NREG, target_elf_greg_t, and tswapreg.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2 files changed