bsd-user: arm (32-bit) support
This series of patches brings in 32-bit arm support for bsd-user. It implements
all the bits needed to do image activation, signal handling, stack management
and threading. This allows us to get to the "Hello World" level. The arm and x86
code are now the same as in the bsd-user fork. For full context, the fork is at
https://github.com/qemu-bsd-user/qemu-bsd-user/tree/blitz (though the the recent
sig{bus,segv} needed updates are incomplete).
v5 changes:
o Moved to using the CPUArchState typedef and move
set_sigtramp_args, get_mcontext, set_mcontext, and
get_ucontext_sigreturn prototypes to
bsd-user/freebsd/target_os_ucontext.h
o Fix issues with arm's set_mcontext related to masking
and remove an unnecessary check.
We're down to only one hunk needing review:
bsd-user/arm/target_arch_signal.c: arm set_mcontext
Warnings that should be ignored:
o make checkpatch has a couple of complaints about the comments for the
signal trampoline, since it's a false positive IMHO.
WARNING: Block comments use a leading /* on a separate line
+ /* 8 */ sys_sigreturn,
WARNING: Block comments use a leading /* on a separate line
+ /* 9 */ sys_exit