bpf: doc: correct arch list for supported eBPF JIT

aarch64 and s390x support eBPF JIT too, correct document to reflect this and
avoid any confusion.

Signed-off-by: Yang Shi <yang.shi@linaro.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/filter.txt

@@ -596,9 +596,9 @@ skb pointer). All constraints and restrictions from bpf_check_classic() apply
 before a conversion to the new layout is being done behind the scenes!
 
 Currently, the classic BPF format is being used for JITing on most of the
-architectures. Only x86-64 performs JIT compilation from eBPF instruction set,
-however, future work will migrate other JIT compilers as well, so that they
-will profit from the very same benefits.
+architectures. x86-64, aarch64 and s390x perform JIT compilation from eBPF
+instruction set, however, future work will migrate other JIT compilers as well,
+so that they will profit from the very same benefits.
 
 Some core changes of the new internal format: