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>
diff --git a/drivers/bus/Makefile b/drivers/bus/Makefile
index 1c29c5e..52c2f35 100644
--- a/drivers/bus/Makefile
+++ b/drivers/bus/Makefile
@@ -27,7 +27,7 @@
 obj-$(CONFIG_QCOM_EBI2)		+= qcom-ebi2.o
 obj-$(CONFIG_SUN50I_DE2_BUS)	+= sun50i-de2.o
 obj-$(CONFIG_SUNXI_RSB)		+= sunxi-rsb.o
-obj-$(CONFIG_SIMPLE_PM_BUS)	+= simple-pm-bus.o
+obj-$(CONFIG_OF)		+= simple-pm-bus.o
 obj-$(CONFIG_TEGRA_ACONNECT)	+= tegra-aconnect.o
 obj-$(CONFIG_TEGRA_GMI)		+= tegra-gmi.o
 obj-$(CONFIG_TI_PWMSS)		+= ti-pwmss.o