Merge tag 'please-pull-pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux

Pull pstore updates from Tony Luck:
 "Half dozen small cleanups plus change to allow pstore backend drivers
  to be unloaded"

* tag 'please-pull-pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
  pstore: fix code comment to match code
  efi-pstore: fix kernel-doc argument name
  pstore: Fix return type of pstore_is_mounted()
  pstore: add pstore unregister
  pstore: add a helper function pstore_register_kmsg
  pstore: add vmalloc error check