[automerger skipped] Update bootloader, u-boot tools to builds 7833660 am: f6829c7a67 -s ours am: 827dc7f328 -s ours am: fa4571d312 -s ours

am skip reason: Merged-In Iae4fe2a0b10c57b79d8185a52d05c679c7a31021 with SHA-1 bab925d0d0 is already in history

Original change: https://android-review.googlesource.com/c/device/google/cuttlefish_prebuilts/+/1864218

Change-Id: I1a82f5ef4d18f37bbe26b279ec2433c5bb83ddd6