bpf: move explored_state() closer to the beginning of verifier.c

Subsequent patches would make use of explored_state() function.
Move it up to avoid adding unnecessary prototype.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20231024000917.12153-2-eddyz87@gmail.comSigned-off-by: Alexei Starovoitov <ast@kernel.org>

kernel/bpf/verifier.c

@@ -1817,6 +1817,19 @@ static int copy_verifier_state(struct bpf_verifier_state *dst_state,
 	return 0;
 }
 
+static u32 state_htab_size(struct bpf_verifier_env *env)
+{
+	return env->prog->len;
+}
+
+static struct bpf_verifier_state_list **explored_state(struct bpf_verifier_env *env, int idx)
+{
+	struct bpf_verifier_state *cur = env->cur_state;
+	struct bpf_func_state *state = cur->frame[cur->curframe];
+
+	return &env->explored_states[(idx ^ state->callsite) % state_htab_size(env)];
+}
+
 static void update_branch_counts(struct bpf_verifier_env *env, struct bpf_verifier_state *st)
 {
 	while (st) {
@@ -15020,21 +15033,6 @@ enum {
 	BRANCH = 2,
 };
 
-static u32 state_htab_size(struct bpf_verifier_env *env)
-{
-	return env->prog->len;
-}
-
-static struct bpf_verifier_state_list **explored_state(
-					struct bpf_verifier_env *env,
-					int idx)
-{
-	struct bpf_verifier_state *cur = env->cur_state;
-	struct bpf_func_state *state = cur->frame[cur->curframe];
-
-	return &env->explored_states[(idx ^ state->callsite) % state_htab_size(env)];
-}
-
 static void mark_prune_point(struct bpf_verifier_env *env, int idx)
 {
 	env->insn_aux_data[idx].prune_point = true;