ARM/THUMB long calls stubs

[Richard Earnshaw]

> 
> By way of a suggestion, how about the _call_via.. functions be made 
> inline? Is there an option to do this? (Could somebody very quickly 
> write a patch to allow this ;-) ??
> 

The whole point of the _call_via instructions is to get the current PC in 
r14 without losing the Thumb bit.  This can only be do with a BL 
instruction, so we must call something.  If it weren't for the fact that 
mov lr, pc lost the thumb bit we could just write

	mov	lr, pc
	bx	Rn

R.

PS In V5 we can do

	blx	Rn

and the problem is solved.