hostapd: Avoid channel selection across underlying hardware index

hostapd: Avoid channel selection across underlying hardware index

Currently, channel is selected from the current hw_mode. However, not
all channels under current hw_mode might be available for the current
operating underlying hardware.

Add logic to check if the selected channel falls under the current
operating hardware index and only if so, continue with the selected
channel.

Co-developed-by: Harshitha Prem <quic_hprem@quicinc.com>
Signed-off-by: Harshitha Prem <quic_hprem@quicinc.com>
Signed-off-by: Aditya Kumar Singh <quic_adisi@quicinc.com>