drivers: bus: Delete CONFIG_SIMPLE_PM_BUS

drivers: bus: Delete CONFIG_SIMPLE_PM_BUS

The simple-pm-bus driver is mandatory for CONFIG_OF based platforms to work
with fw_devlink. So, always compile it in for CONFIG_OF and delete the
config since it's no longer necessary.

Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Damien Le Moal <damien.lemoal@wdc.com>
Cc: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20210929000735.585237-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>