bpf: fix spelling mistake: "funcation"-> "function"

Trivial fix to spelling mistake in error message text.
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

kernel/bpf/verifier.c

@@ -772,7 +772,7 @@ static int check_subprogs(struct bpf_verifier_env *env)
 			return -EPERM;
 		}
 		if (bpf_prog_is_dev_bound(env->prog->aux)) {
-			verbose(env, "funcation calls in offloaded programs are not supported yet\n");
+			verbose(env, "function calls in offloaded programs are not supported yet\n");
 			return -EINVAL;
 		}
 		ret = add_subprog(env, i + insn[i].imm + 1);