configs/microchip_sam9x60ek: new defconfigs

Add the new SAM9X60 Evaluation Kit with linux4sam_2020.04
components.  Update README file with new defconfigs.

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

board/atmel/readme.txt

@@ -21,6 +21,8 @@ This guide covers the following configurations:
  - atmel_sama5d2_xplained_mmc_dev_defconfig
  - microchip_sama5d27_wlsom1_ek_mmc_defconfig
  - microchip_sama5d27_wlsom1_ek_mmc_dev_defconfig
+ - microchip_sam9x60ek_mmc_defconfig
+ - microchip_sam9x60ek_mmc_dev_defconfig
 
 These configurations will use AT91Bootstrap, u-boot and a linux kernel from
 the git trees maintained by Atmel.

board/microchip/sam9x60ek_mmc/genimage.cfg

@@ -0,0 +1,31 @@
+# Image for SD card boot on Microchip SAM9X60-EK
+#
+image boot.vfat {
+	vfat {
+		files = {
+			"zImage",
+			"at91-sam9x60ek.dtb",
+			"boot.bin",
+			"u-boot.bin"
+		}
+	}
+	size = 16M
+}
+
+image sdcard.img {
+	hdimage {
+	}
+
+	partition boot {
+		partition-type = 0xC
+		bootable = "true"
+		image = "boot.vfat"
+		offset = 1M
+	}
+
+	partition rootfs {
+		partition-type = 0x83
+		image = "rootfs.ext4"
+		size = 512M
+	}
+}