[nrf fromtree] tests: drivers: spi: Add support ek_ra2l1 for spi_loopback test

Add support for ek_ra2l1 on spi_loopback.

Signed-off-by: Thao Luong <[email protected]>
(cherry picked from commit e2267bd)

Author: thaoluonguw

tests/drivers/spi/spi_loopback/boards/ek_ra2l1.conf

@@ -0,0 +1,3 @@
+CONFIG_SPI_LOOPBACK_MODE_LOOP=y
+CONFIG_SPI_INTERRUPT=y
+CONFIG_SPI_RA_DTC=y

tests/drivers/spi/spi_loopback/boards/ek_ra2l1.overlay

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2025 Renesas Electronics Corporation
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+&spi0 {
+	rx-dtc;
+	tx-dtc;
+
+	slow@0 {
+		compatible = "test-spi-loopback-slow";
+		reg = <0>;
+		spi-max-frequency = <2000000>;
+	};
+
+	fast@0 {
+		compatible = "test-spi-loopback-fast";
+		reg = <0>;
+		spi-max-frequency = <3000000>;
+	};
+};
+
+&pinctrl {
+	spi0_default: spi0_default {
+		group1 {
+			/* MISO MOSI RSPCK */
+			psels = <RA_PSEL(RA_PSEL_SPI, 1, 0)>,
+			<RA_PSEL(RA_PSEL_SPI, 1, 1)>,
+			<RA_PSEL(RA_PSEL_SPI, 1, 2)>;
+		};
+	};
+};
+
+&spi0 {
+	pinctrl-0 = <&spi0_default>;
+	pinctrl-names = "default";
+	cs-gpios = <&ioport1 3 GPIO_ACTIVE_LOW>;
+	interrupts = <8 1>, <9 1>, <10 1>, <19 1>;
+	interrupt-names = "rxi", "txi", "tei", "eri";
+	status = "okay";
+};
+
+&ioport1 {
+	status = "okay";
+};