arm64: defconfig: Enable devfreq support for i.MX8MQ

This is needed to make DRAM frequency scaling via devfreq as used
on the Librem 5 and Librem 5 Devkit.

With the interconnect support enabled we now need imx devfreq on top
to make this work.
Signed-off-by: Guido Günther <agx@sigxcpu.org>
Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/configs/defconfig

@@ -1022,6 +1022,8 @@ CONFIG_ARCH_TEGRA_186_SOC=y
 CONFIG_ARCH_TEGRA_194_SOC=y
 CONFIG_ARCH_TEGRA_234_SOC=y
 CONFIG_TI_SCI_PM_DOMAINS=y
+CONFIG_ARM_IMX_BUS_DEVFREQ=m
+CONFIG_ARM_IMX8M_DDRC_DEVFREQ=m
 CONFIG_EXTCON_PTN5150=m
 CONFIG_EXTCON_USB_GPIO=y
 CONFIG_EXTCON_USBC_CROS_EC=y