configs/rock_pi_4_defconfig: remove BR2_TARGET_UBOOT_NEEDS_PYTHON
BR2_TARGET_UBOOT_NEEDS_PYTHON3 is already selected for
this defconfig, BR2_TARGET_UBOOT_NEEDS_PYTHON and
BR2_TARGET_UBOOT_NEEDS_PYTHON3 can't be selected at the
same time.
Reported by check-dotconfig.py.
Fixes:
https://gitlab.com/kubu93/buildroot/-/jobs/657885313
Signed-off-by: Romain Naour <romain.naour@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>