[Buildroot] [PATCH v1 2/4] configs/zynq_zed_defconfig: bump to Xilinx 2021.2

[Neal Frager]

Hi Arnout,

> +BR2_LINUX_KERNEL_CUSTOM_GIT=y
> +BR2_LINUX_KERNEL_CUSTOM_REPO_URL="https://github.com/Xilinx/linux-xlnx.git"

>   We generally prefer to use the upstream kernel rather than a vendor kernel - if it works of course. Is the vendor kernel dramatically better than upstream?

I understand.  Unfortunately, not all of the zynq and zynqmp peripheral drivers are fully upstream to mainline.
This often causes support issues on our side.  Specifically for peripherals like usb and qspi.
Developers are certainly free to choose whichever u-boot or Linux kernel version they want.
However, I see these defconfigs as promotional examples of how to use Xilinx zynq SoCs on our evaluation boards.
Since we only perform production and regression testing on our software releases, 
my preference would be to keep the Xilinx defconfigs on the Xilinx github for now.

> +BR2_LINUX_KERNEL_CUSTOM_REPO_VERSION="xlnx_rebase_v5.10_2021.2"

>  There's also a xilinx-v2021.2 tag, which sounds more like what we'd want to use.

The xilinx-v2021.2 tag is functionally identical to the xlnx_rebase_v5.10_2021.2 tag.
I tend to like the xlnx_rebase_v5.10_2021.2 tag name because it includes the Linux kernel version in the tag name.
Same comment for the xlnx_rebase_v2021.01_2021.2 u-boot tag name.

Best regards,
Neal Frager
AMD