mei: wd: drop AGAIN the watchdog code from the core mei driver

The file wd.c was remove from the driver by commit
commit fdd9b865 ("mei: wd: drop the watchdog code from the core mei
driver")

Unfortunately it came back by mistake in rebasing in the commit
commit 06ee536b ("mei: fill file pointer in read cb for fixed
address client")

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>