[PATCH] Add support for parsing ARM symbol variants on ELF targets

[Tim Northover]

Hi David,

> ARM symbol variants are written with parens instead of @ like this:
>
>   .word __GLOBAL_I_a(target1)

I don't think this is universally true. At least Joerg today was
talking about an @GOT symbol that we didn't support.

Separately I think the relocation in the @PLT case is dodgy.
R_ARM_PLT32 is deprecated according to the ARM ELF ABI. R_ARM_CALL
should be used instead (much like R_ARM_THM_CALL is used in the thumb
case). I'd advocate this regardless of what binutils did, but it
appears my copy of binutils-2.23 agrees.

Cheers.

Tim.