arm64: defconfig: add CONFIG_BRCMSTB_THERMAL

Turn on CONFIG_BRCMSTB_THERMAL as module.
Signed-off-by: Markus Mayer <mmayer@broadcom.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

arch/arm64/configs/defconfig

@@ -304,6 +304,7 @@ CONFIG_SENSORS_INA2XX=m
 CONFIG_THERMAL_GOV_POWER_ALLOCATOR=y
 CONFIG_CPU_THERMAL=y
 CONFIG_THERMAL_EMULATION=y
+CONFIG_BRCMSTB_THERMAL=m
 CONFIG_EXYNOS_THERMAL=y
 CONFIG_ROCKCHIP_THERMAL=m
 CONFIG_WATCHDOG=y