boot/uboot: bump to version 2025.07

Release announcement:
https://lists.denx.de/pipermail/u-boot/2025-July/593789.html

Changelog:
https://github.com/u-boot/u-boot/compare/v2025.04...v2025.07



Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Julien Olivain <ju.o@free.fr>