bpf: KVER_5_9 -> KVER_5_10

5.9 is not LTS, and thus isn't supported.
Let's simplify to 5.10 which is the actual LTS supported version.

Test: TreeHugger
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I5595abaacb9b479d82787dc021b0e3109a49951d
diff --git a/bpf/progs/offload.c b/bpf/progs/offload.c
index 9a1d26c..0f23844 100644
--- a/bpf/progs/offload.c
+++ b/bpf/progs/offload.c
@@ -805,7 +805,7 @@
 }
 
 #define DEFINE_XDP_PROG(str, func) \
-    DEFINE_BPF_PROG_KVER(str, AID_ROOT, AID_NETWORK_STACK, func, KVER_5_9)(struct xdp_md *ctx)
+    DEFINE_BPF_PROG_KVER(str, AID_ROOT, AID_NETWORK_STACK, func, KVER_5_10)(struct xdp_md *ctx)
 
 DEFINE_XDP_PROG("xdp/tether_downstream_ether",
                  xdp_tether_downstream_ether) {