Pull smack updates from James Morris:
 "From Casey: three patches for Smack for 4.20. Two clean up warnings
  and one is a rarely encountered ptrace capability check"

* 'next-smack' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  Smack: Mark expected switch fall-through
  Smack: ptrace capability use fixes
  Smack: remove set but not used variable 'root_inode'