Enable serial driver to be built as a module. To do so, init the console
support on driver/module load instead of using console_initcall().

Inspired by commit 87a0b9f9 ("tty: serial: meson: enable console as
module").
Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20211204195757.8600-5-semen.protsenko@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>