[PATCH] tpm: fix memory leak

The eventname was kmalloc'd and not freed in the *_show functions.

This bug was found by Coverity.

Signed-off-by: Kylene Hall <kjhall@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>