[uboot] create uboot from github:

repo: https://github.com/u-boot/u-boot
	commit: d80bb749fab53da72c4a0e09b8c2d2aaa3103c91

Change-Id: Ie6434426e1ec15bc08bb1832798e371f3fd5fb29

u-boot-2021.10/include/android_ab.h

@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ */
+
+#ifndef __ANDROID_AB_H
+#define __ANDROID_AB_H
+
+struct blk_desc;
+struct disk_partition;
+
+/* Android standard boot slot names are 'a', 'b', 'c', ... */
+#define BOOT_SLOT_NAME(slot_num) ('a' + (slot_num))
+
+/* Number of slots */
+#define NUM_SLOTS 2
+
+/**
+ * Select the slot where to boot from.
+ *
+ * On Android devices with more than one boot slot (multiple copies of the
+ * kernel and system images) selects which slot should be used to boot from and
+ * registers the boot attempt. This is used in by the new A/B update model where
+ * one slot is updated in the background while running from the other slot. If
+ * the selected slot did not successfully boot in the past, a boot attempt is
+ * registered before returning from this function so it isn't selected
+ * indefinitely.
+ *
+ * @param[in] dev_desc Place to store the device description pointer
+ * @param[in] part_info Place to store the partition information
+ * @return The slot number (>= 0) on success, or a negative on error
+ */
+int ab_select_slot(struct blk_desc *dev_desc, struct disk_partition *part_info);
+
+#endif /* __ANDROID_AB_H */