board/xilinx: remove Linux 2024.2 hash

Now that all of the Xilinx boards have been bumped to Linux 6.6.60, the
Linux 2024.2 (6.6.40) hash can be removed.

Signed-off-by: Neal Frager <neal.frager@amd.com>
Signed-off-by: Julien Olivain <ju.o@free.fr>

board/xilinx/patches/linux/linux.hash

@@ -1,3 +1,2 @@
 # Locally calculated
-sha256  8ebbbe2d40597d9a5f36d47a1dfe4caffcef3d9f5ffa059ed4504bb761282593  xlnx_rebase_v6.6_LTS_2024.2.tar.gz
 sha256  f59c7d260794d73ee519ba2579ef41aa8ac4985ac5af9461f94fa314969acd2e  xlnx_rebase_v6.6_LTS_merge_6.6.60.tar.gz