Remove forced frequency for Wi-Fi P2P group

Remove forced frequency for Wi-Fi P2P group

Description: When device doesn't support multi channel concurrent
and connected to Ap, user shouldn't add frequency information for
GruopAdd method. Because wpasupplicant won't selected shared frequency
but it chooses the random chennel if frequecny is given as 2.

P2P: Request to start GO on 2.4 GHz band
P2P: Use random 2.4 GHz band channel: 2412 MHz
p2p0: Determining shared radio frequencies (max len 1)
p2p0: Shared frequencies (len=1): completed iteration
p2p0: freq[0]: 2472, flags=0x1
p2p0: Shared frequencies (len=1): valid for P2P
p2p0: freq[0]: 2472, flags=0x1
p2p0: P2P: Common group frequencies (len=0):
p2p0: Determining shared radio frequencies (max len 1)
p2p0: Shared frequencies (len=1): completed iteration
p2p0: freq[0]: 2472, flags=0x1
p2p0: P2P: num_unused_channels: 0
P2P: Cannot force GO on freq (2412 MHz) as all the channels are in use

Change-Id: I1fd3c2f21c2265ae5e86dfd42220511bfaf78ba6
Signed-off-by: Yu jiung <jiung.yu@samsung.com>