ath11k: Rename atf_config to flag1 in target_resource_config

The flag's purpose is not only meant for ATF configs. Rename atf_config
to flag1, so it can be used for future purposes.

Tested-on: IPQ8074 hw2.0 AHB WLAN.HK.2.1.0.1-01228-QCAHKSWPL_SILICONZ-1

Signed-off-by: Seevalamuthu Mariappan <seevalam@codeaurora.org>
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210720214922.118078-1-jouni@codeaurora.org