bus: davinci: add support for da8xx bus master priority control

Create the driver for the da8xx master peripheral priority
configuration and implement support for writing to the three
Master Priority registers on da850 SoCs.

Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
[nsekhar@ti.com: subject line adjustment]
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig
index 7010dca..ed6a89c 100644
--- a/drivers/bus/Kconfig
+++ b/drivers/bus/Kconfig
@@ -166,4 +166,13 @@
 	help
 	  Platform configuration infrastructure for the ARM Ltd.
 	  Versatile Express.
+
+config DA8XX_MSTPRI
+	bool "TI da8xx master peripheral priority driver"
+	depends on ARCH_DAVINCI_DA8XX
+	help
+	  Driver for Texas Instruments da8xx master peripheral priority
+	  configuration. Allows to adjust the priorities of all master
+	  peripherals.
+
 endmenu