Hi,

sid, <target>-sid and siddoc were being installed as <target>-sid, 
<target>-<target>-sid and <target>-siddoc respectively.

For example: xstormy16-elf-sid, xstormy16-elf-xstormy16-elf-sid and 
xstormy16-elf-siddoc

I've committed this patch which corrects this problem.

Dave