boards: renesas: rzg3s_smarc: Add interrupt controller support

Add interrupt controller support for board RZ/G3S-SMARC

Signed-off-by: Hoang Nguyen <hoang.nguyen.jx@bp.renesas.com>
Signed-off-by: Nhut Nguyen <nhut.nguyen.kc@renesas.com>

Author: Hoang Nguyen

boards/renesas/rzg3s_smarc/doc/index.rst

@@ -71,6 +71,8 @@ and the following hardware features:
 +-----------+------------+-------------------------------------+
 | GPT       | on-chip    | pwm                                 |
 +-----------+------------+-------------------------------------+
+| INTC      | on-chip    | external interrupt controller       |
++-----------+------------+-------------------------------------+
 
 Other hardware features are currently not supported by the port.