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/Makefile b/drivers/sysreset/Makefile
index 7bb8406..bd352e7 100644
--- a/drivers/sysreset/Makefile
+++ b/drivers/sysreset/Makefile
@@ -6,6 +6,7 @@
 
 obj-$(CONFIG_SYSRESET) += sysreset-uclass.o
 obj-$(CONFIG_SYSRESET_PSCI) += sysreset_psci.o
+obj-$(CONFIG_SYSRESET_SYSCON) += sysreset_syscon.o
 
 ifndef CONFIG_SPL_BUILD
 obj-$(CONFIG_ROCKCHIP_RK3036) += sysreset_rk3036.o