RFA: ARM: Implement __builtin_trap

[Anton Korobeynikov]

> Specifically, the LLVM backend emits:
>
> _t:                                     @ @t
>        .long 0xe7ffdefe @ trap
>
>
> So no, I don't think that trap is a standard mnemonic.
iirc "trap" is supported as a separate mnemonic in darwin as. gas does
not support it, thus we emit .word / .long here


-- 
With best regards, Anton Korobeynikov
Faculty of Mathematics and Mechanics, Saint Petersburg State University