also, on ARM, inline(always) the actual implementation of the intrinsics so we
end with code like this:

```
00000000 <__aeabi_dadd>:
    (implementation here)
```

instead of "trampolines" like this:

```
00000000 <__aeabi_dadd>:
    (shuffle registers)
    (call __adddf3)

00000000 <__adddf3>:
    (implementation here)
```

closes #116

- multi3: there's no aeabi equivalent
- divmod{s,d}i4: these are directly called by __aeabi_{l,i}divmod
- add{s,d}f3: required by the C sub{s,d}f3 implementation

but make sure they also use the AAPCS calling convention