s390/bpf: Fix a typo in a comment

"desription" should be "description".

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20230128000650.1516334-27-iii@linux.ibm.com


Signed-off-by: Alexei Starovoitov <ast@kernel.org>