ath9k_hw: Fix MCI init for AGC calibration

When AGC calibration is to be done, a GPM message with the
payload, MCI_GPM_WLAN_CAL_REQ has to be sent. Currently this falls
within the IQ-CAL code block which is incorrect. Fix this by using
a separate variable to decide when IQ-CAL is to be done separately
and call ar9003_mci_init_cal_req correctly.

Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>