[poppler] Increase %%EOF searching

[Kristian Høgsberg]

Albert Astals Cid wrote:
> Ok, finally i've come across a document that has %%EOF VEEEEEEEEERY far from 
> the end but still in the last 1024 bytes pdf spec says adobe checks for.
> 
> Agree to commit?

It looks good to me, except, what happens for documents smaller that 
1024 bytes?  We should probably break out of the for loop on EOF and 
nul-terminate the buffer.

Kristian