rsi: Assign beacon rate settings to the correct rate_info descriptor field

The RSI_RATE_x bits must be assigned to struct rsi_data_desc rate_info
field. The rest of the driver does it correctly, except this one place,
so fix it. This is also aligned with the RSI downstream vendor driver.
Without this patch, an AP operating at 5 GHz does not transmit any
beacons at all, this patch fixes that.

Fixes: d26a9559 ("rsi: add beacon changes for AP mode")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Amitkumar Karwar <amit.karwar@redpinesignals.com>
Cc: Angus Ainslie <angus@akkea.ca>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: Karun Eagalapati <karun256@gmail.com>
Cc: Martin Kepplinger <martink@posteo.de>
Cc: Prameela Rani Garnepudi <prameela.j04cs@gmail.com>
Cc: Sebastian Krzyszkowiak <sebastian.krzyszkowiak@puri.sm>
Cc: Siva Rebbagondla <siva8118@gmail.com>
Cc: netdev@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210507213105.140138-1-marex@denx.de