Blackfin: support L2 memory

[Jie Zhang]

Bernd Schmidt wrote:
> Joseph S. Myers wrote:
>> On Fri, 11 Sep 2009, Bernd Schmidt wrote:
>>
>>> This patch by Jie Zhang allows us to place sections into L2 memory (a
>>> piece of SRAM on certain chips).  Committed.
>> This patch is missing documentation for the new attribute in extend.texi 
>> and testcases for the testsuite that valid cases of the attribute are 
>> accepted with the desired effect and invalid cases are rejected.
> 
> I found the docs commit in our tree and committed it, as below.
> Jie, could you do a testcase?
> 
OK. I'll do it next week.

Jie