Coverity found bugs

[Joel Schopp]

I recently got Coverity Prevent ( http://coverity.com/ ) for x86 Linux. 
  Through the modern miracle of cross compiling I got it to spit out 
what it thinks are errors in the ppc64 kernel.  Hundreds of them.  I 
plan on fixing as many of these as I have time for, starting with the 
arch specific ones, which I will post as replies to this message.  I 
will leave individual fixes in individual patches for now, but if it 
starts to get excessive I will group batches of them into single patches.