wpa_supplicant: "don't care" value for pbss in ssid structure

wpa_supplicant: "don't care" value for pbss in ssid structure

Add a new value 2 to the pbss parameter of wpa_ssid structure, which
means "don't care". This value is used in infrastructure mode to request
connection to either AP or PCP, whichever is available in the scan
results. The value is also used in regular WPS (not P2P group formation)
to make WPS work with devices running as either AP or PCP.

Signed-off-by: Lior David <qca_liord@qca.qualcomm.com>