staging: vc04_services: no need to save the log debufs dentries

The log entry dentries are only set, never referenced, so no need to
keep them around.  Remove the pointer from struct
vchiq_debugfs_log_entry as it is not needed anymore and get rid of the
separate vchiq_debugfs_create_log_entries() function as it is only used
in one place.

Suggested-by: Eric Anholt <eric@anholt.net>
Cc: Stefan Wahren <stefan.wahren@i2se.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Keerthi Reddy <keerthigd4990@gmail.com>
Cc: linux-rpi-kernel@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>