sysreset: add syscon-reboot driver

Add a new sysreset driver based on linux/drivers/power/reset/syscon-reboot.c,
which provides a generic driver for platforms that only require writing a mask
to a regmap offset.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/sysreset/Kconfig b/drivers/sysreset/Kconfig
index 9664630..b2f7464 100644
--- a/drivers/sysreset/Kconfig
+++ b/drivers/sysreset/Kconfig
@@ -23,4 +23,12 @@
 	  must be running on your system.
 
 endif
+
+config SYSRESET_SYSCON
+	bool "Enable support for mfd syscon reboot driver"
+	select REGMAP
+	select SYSCON
+	help
+	  Reboot support for generic SYSCON mapped register reset.
+
 endmenu