Replaced [u_]arg() with [u]int_arg(), [u]long_arg(), {s|u}32_arg(),

Replaced [u_]arg() with [u]int_arg(), [u]long_arg(), {s|u}32_arg(),
{s|u}64_arg(), etc.  Added asmlinkage(), fastcall(), regparm().
Dealt with some surprises -- e.g., rax is ZERO-extended eax.
Seems to work well with -m32 and -m64 user apps, and with a (small)
dwarfless subset of syscall.stp.