brcmfmac: prohibit ACPI power management for brcmfmac driver

ACPI will manage WiFi chip's power state during suspend/resume
process on some tablet platforms(such as ASUS T100TA). This is
not supported by brcmfmac driver now, and the context of WiFi
chip will be damaged after resume. This patch informs ACPI not
to manage WiFi chip's power state.

Signed-off-by: Zhonghui Fu <zhonghui.fu@linux.intel.com>
Acked-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>