[PATCH] Fix Thumb-2 JUMP19 relocation

[Mark Shinwell]

Mark Shinwell wrote:
> The current handling of the Thumb-2 JUMP19 relocation (used for
> certain conditional branches) is rather broken.  There are several
> errors, one particularly subtle one being the incorrect use of ~
> rather than ! when performing a sign extension.
> 
> This patch fixes the problems; I also hope it makes the code a
> bit easier to understand.  OK to apply?

Ping.