Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild

Pull kbuild changes from Michal Marek:
 "The kbuild changes are minimal this time:

   - scripts/pnmlogo fix for some newer format

   - minor top-level Makefile cleanup

   - fix for a v3.5 regression with make clean M=<directory>"

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild: Do not remove vmlinux when cleaning external module
  scripts/pnmtologo: fix for plain PBM
  kbuild: Remove reference to uninitialised variable