arch: rework/fix the arch-syscall-validate script
arch: rework/fix the arch-syscall-validate script

Update the arch-syscall-validate script to be "CSV friendly" in
preparation for follow-up work to move the libseccomp internal
syscall tables into a single CVS file.  In this process of making
this change, a number of unrelated problems with the script were
identified and fixed.

Signed-off-by: Paul Moore <a027184a55211cd23e3f3094f1fdc728df5e0500@paul-moore.com>

seccomp/libseccomp,seccomp/libseccomp,seccomp/libseccomp