For readability, define a tpm_chip_put() wrapper to call module_put().
Replace existing module_put() calls with the wrapper.

(Change based on trusted/encrypted patchset review by David Howells.)
Signed-off-by: NMimi Zohar <zohar@us.ibm.com>
Signed-off-by: NDavid Safford <safford@watson.ibm.com>
Acked-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NSerge E. Hallyn <serge.hallyn@canonical.com>
Signed-off-by: NJames Morris <jmorris@namei.org>