timer: renesas: Add RZ/A1 R7S72100 OSTM timer driver

Add OSTM timer driver for RZ/A1 SoC. The IP is very different
from the R-Car Gen2/Gen3 one already present in the tree, hence
a custom driver.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Chris Brandt <chris.brandt@renesas.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
diff --git a/drivers/timer/Makefile b/drivers/timer/Makefile
index d0bf218..fa35bea 100644
--- a/drivers/timer/Makefile
+++ b/drivers/timer/Makefile
@@ -13,6 +13,7 @@
 obj-$(CONFIG_DESIGNWARE_APB_TIMER)	+= dw-apb-timer.o
 obj-$(CONFIG_MPC83XX_TIMER) += mpc83xx_timer.o
 obj-$(CONFIG_OMAP_TIMER)	+= omap-timer.o
+obj-$(CONFIG_RENESAS_OSTM_TIMER) += ostm_timer.o
 obj-$(CONFIG_RISCV_TIMER) += riscv_timer.o
 obj-$(CONFIG_ROCKCHIP_TIMER) += rockchip_timer.o
 obj-$(CONFIG_SANDBOX_TIMER)	+= sandbox_timer.o