Pull powerpc build fixes from Stephen Rothwell:
"Just a couple of build fixes for powerpc all{mod,yes}config.
Submitted by me since BenH is on vacation."
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sfr/next-fixes:
powerpc: define the conditions where the ePAPR idle hcall can be supported
powerpc: make additional room in exception vector area