Modify the syscalls script to generate the cfi directives for x86
syscalls.
Update the x86 syscalls.
Change-Id: Ia1993dc714a7e79f917087fff8200e9a02c52603
We only need it for MAX_ERRNO, and it's time we had somewhere to put
the little assembler utility macros we've been putting off writing.
Change-Id: I9354d2e0dc47c689296a34b5b229fc9ba75f1a83
I've left the exit_group syscall as _exit because otherwise we'd have to
convince the compiler that our _exit (which just calls __exit_group) is
actually "noreturn", and it seems like that would be less clean than just
cutting out the middleman.
We'll just have to trust ourselves not to add anything to SYSCALLS.TXT
that ought to be private but that only has a single leading underscore.
Hopefully we can manage that.
Change-Id: Iac47faea9f516186e1774381846c54cafabc4354
