Add new QCA vendor roam control attributes

Add new QCA vendor roam control attributes

Add new roam control vendor attributes to configure the roaming
parameters dynamically.
QCA_ATTR_ROAM_CONTROL_CANDIDATE_SCORE_WEIGHTAGE_2P4GHZ,
QCA_ATTR_ROAM_CONTROL_CANDIDATE_SCORE_WEIGHTAGE_5GHZ and
QCA_ATTR_ROAM_CONTROL_CANDIDATE_SCORE_WEIGHTAGE_6GHZ controls the
band weightage given for candidate APs on 2.4 GHz, 5 GHz and 6 GHz
respectively.
QCA_ATTR_ROAM_CONTROL_CANDIDATE_SCORE_THRESHOLD_PERCENTAGE
controls the minimum required score threshold in percentage for an AP to
be considered as a roaming candidate.
QCA_ATTR_ROAM_CONTROL_CONNECTED_LOW_RSSI_THRESHOLD_DECREMENT configures
the decremental RSSI value to be used for next low RSSI roam scan
trigger.
QCA_ATTR_ROAM_CONTROL_PERIODIC_ROAM_SCAN_INTERVAL sets the
interval for repeated roam scans until a candidate found.

Signed-off-by: Kashish Awasthi <quic_kawasthi@quicinc.com>