board/qemu/aarch64-virt/linux.config: enable QEMU firmware configuration (fw_cfg)
>From [1]:
This kernel option allow exporting of the QEMU firmware configuration (fw_cfg)
file entries via sysfs. Entries are found under /sys/firmware/fw_cfg when this
option is enabled and loaded.
Enable the suboption to allow the qemu_fw_cfg device to be initialized via the
kernel command line or using a module parameter.
[1] https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/drivers/firmware/Kconfig?h=v5.4.42#n187
Signed-off-by: Romain Naour <romain.naour@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>