bootcount: add a new driver with syscon as backend

The driver will use a syscon regmap as backend and supports both
16 and 32 size value. The value will be stored in the CPU's endianness.

Signed-off-by: Nandor Han <nandor.han@vaisala.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/bootcount/Makefile b/drivers/bootcount/Makefile
index 12658ff..3a784bb 100644
--- a/drivers/bootcount/Makefile
+++ b/drivers/bootcount/Makefile
@@ -14,3 +14,4 @@
 obj-$(CONFIG_DM_BOOTCOUNT_RTC)  += rtc.o
 obj-$(CONFIG_DM_BOOTCOUNT_I2C_EEPROM)	+= i2c-eeprom.o
 obj-$(CONFIG_DM_BOOTCOUNT_SPI_FLASH)	+= spi-flash.o
+obj-$(CONFIG_DM_BOOTCOUNT_SYSCON) += bootcount_syscon.o