LOWI messages to register, set capability
and send RTT measurement request are not sent assuming only
LCI and LCR messages are sent out to the FW using ol_ath_lowi_data_req_to_fw.
Add code to send messages other than LCI and LCR through the API in
ol_if_lowi.c when msg subtype is not one of LCI or LCR.
Change-Id: I2deedaa6e03e769bf802337b2ec93d9573eb1b5a
CRs-Fixed: 1079169