efi_selftest: check for RISC-V boot-hartid in FDT

On RISC-V check that the /chosen node has a boot-hartid property.

To run the test configure with CONFIG_CMD_BOOTEFI_SELFTEST=y and issue

    setenv efi_selftest device tree
    setenv serial# myserial
    bootefi selftest

If the test succeeds, it reports the boot-hartid, e.g.

    boot-hartid: 1
Signed-off-by: NHeinrich Schuchardt <xypron.glpk@gmx.de>

lib/efi_selftest/efi_selftest_fdt.c

@@ -219,6 +219,21 @@ static int execute(void)
 			return EFI_ST_FAILURE;
 		}
 	}
+	str = get_property(L"boot-hartid", L"chosen");
+	if (IS_ENABLED(CONFIG_RISCV)) {
+		if (str) {
+			efi_st_printf("boot-hartid: %u\n",
+				      f2h(*(fdt32_t *)str));
+			ret = boottime->free_pool(str);
+			if (ret != EFI_SUCCESS) {
+				efi_st_error("FreePool failed\n");
+				return EFI_ST_FAILURE;
+			}
+		} else {
+			efi_st_error("boot-hartid not found\n");
+			return EFI_ST_FAILURE;
+		}
+	}
 
 	return EFI_ST_SUCCESS;
 }