PDP-11 bug fix

[Paul Koning]

> On Jan 15, 2020, at 2:32 AM, Lars Brinkhoff <lars@nocrew.org> wrote:
> 
> Hello,
> 
> I originally submitted the PDP-11 target in 2001.  I can't relly
> remember, but possibly I guessed the target page size to be 256.
> As https://sourceware.org/bugzilla/show_bug.cgi?id=20694 explains,
> a better value would be 8192.  Here's a patch:
> ...

256 is clearly not the best value, but the question is whether it should be 64 or 8192.  64 would make sense since that is the start address and length modulus.

	paul