block: drbd: drbd_state: Fix some function documentation issues

Fixes the following W=1 kernel build warning(s):

 drivers/block/drbd/drbd_state.c:913: warning: Function parameter or member 'connection' not described in 'is_valid_soft_transition'
 drivers/block/drbd/drbd_state.c:913: warning: Excess function parameter 'device' description in 'is_valid_soft_transition'
 drivers/block/drbd/drbd_state.c:1054: warning: Function parameter or member 'warn' not described in 'sanitize_state'
 drivers/block/drbd/drbd_state.c:1054: warning: Excess function parameter 'warn_sync_abort' description in 'sanitize_state'
 drivers/block/drbd/drbd_state.c:1703: warning: Function parameter or member 'state_change' not described in 'after_state_ch'

Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Lars Ellenberg <lars.ellenberg@linbit.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: drbd-dev@lists.linbit.com
Cc: linux-block@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210312105530.2219008-5-lee.jones@linaro.org


Signed-off-by: Jens Axboe <axboe@kernel.dk>