mfd: si476x-cmd: Update si476x_cmd_am_rsq_status()'s kerneldoc

mfd: si476x-cmd: Update si476x_cmd_am_rsq_status()'s kerneldoc

4 of the old arguments were grouped and moved into a struct which
is now passed as a pointer instead of the arguments themselves.
However, whoever carried out this work forgot to update the
function's kerneldoc header.

Fixes the following W=1 warnings:

 drivers/mfd/si476x-cmd.c:746: warning: Function parameter or member 'rsqargs' not described in 'si476x_core_cmd_am_rsq_s
 drivers/mfd/si476x-cmd.c:746: warning: Excess function parameter 'rsqack' description in 'si476x_core_cmd_am_rsq_status'
 drivers/mfd/si476x-cmd.c:746: warning: Excess function parameter 'attune' description in 'si476x_core_cmd_am_rsq_status'
 drivers/mfd/si476x-cmd.c:746: warning: Excess function parameter 'cancel' description in 'si476x_core_cmd_am_rsq_status'
 drivers/mfd/si476x-cmd.c:746: warning: Excess function parameter 'stcack' description in 'si476x_core_cmd_am_rsq_status'

Cc: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>