warp7: image_load: Add warp7_image_load.c

This commit adds warp7_image_load.c with the functions

- plat_flush_next_bl_params()
- plat_get_bl_image_load_info()
- plat_get_next_bl_params()
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>

plat/imx/imx7/warp7/warp7_image_load.c

+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <bl_common.h>
+#include <desc_image_load.h>
+#include <platform.h>
+
+void plat_flush_next_bl_params(void)
+{
+	flush_bl_params_desc();
+}
+
+bl_load_info_t *plat_get_bl_image_load_info(void)
+{
+	return get_bl_load_info_from_mem_params_desc();
+}
+
+bl_params_t *plat_get_next_bl_params(void)
+{
+	return get_next_bl_params_from_mem_params_desc();
+}