bcmdhd: set p2p bw 20MHz if wlan0 is on 20MHz.

bcmdhd: set p2p bw 20MHz if wlan0 is on 20MHz.

Default bw will be 40MHz on 5GHz band.
In 2.4 Ghz default bw will be 20 MHz.

Bug 200025947

Change-Id: I28c33c260e0dd8574ea06009b1e817ae843969fb
Signed-off-by: Bibhay Ranjan <bibhayr@nvidia.com>
Reviewed-on: http://git-master/r/494605
(cherry picked from commit 7792e05aa097b1f73c8e7b5c5457e55006cba66a)
Reviewed-on: http://git-master/r/497308
(cherry picked from commit b231dcd7f0cff50199462890750c13c1d2c648ae)
Reviewed-on: http://git-master/r/539884
GVS: Gerrit_Virtual_Submit
Reviewed-by: Dhiren Parmar <dparmar@nvidia.com>