Fix PagedAttention PrevSequenceLengthPattern pattern (openvinotoolkit…

…#24514)

Fix PagedAttention PrevSequenceLengthPattern pattern

Fix pattern of PrevSequenceLengthPattern that makes it match twice than
needed resulting in the incorrect inference.
Provide the correct version of Gather (v8::Gather) and amend
PrevSequenceLengthPattern pattern for the correct matching.

Signed-off-by: Andrii Staikov <[email protected]>

### Details:
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 - *...*

### Tickets:
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Signed-off-by: Andrii Staikov <[email protected]>
Co-authored-by: Ivan Tikhonov <[email protected]>

src/common/transformations/src/transformations/sdpa_to_paged_attention/prev_sequence_length_pattern.cpp

@@ -19,7 +19,7 @@ ov::pass::PrevSequenceLengthPattern::PrevSequenceLengthPattern(
     auto kv_past = pattern::wrap_type<v6::ReadValue>({pattern::any_input()});
     auto kv_gather = pattern::wrap_type<v8::Gather>({kv_past, pattern::any_input(), pattern::any_input()});
     auto kv_shape = pattern::wrap_type<v3::ShapeOf>({kv_gather});
-    auto seq = pattern::wrap_type<v8::Gather>({kv_past, pattern::any_input(), pattern::any_input()});
+    auto seq = pattern::wrap_type<v8::Gather>({kv_shape, pattern::any_input(), pattern::any_input()});
 
     ov::matcher_pass_callback callback = [=](ov::pass::pattern::Matcher& m) {
         // TODO: Check that seq has axis that really takes sequence len but not any other dimension -- use symbolics or

src/core/src/pass/sdpa_to_paged_attention.cpp

@@ -38,7 +38,7 @@ bool ov::pass::SDPAToPagedAttention::run_on_model(const std::shared_ptr<ov::Mode
     };
     auto sliding_window = v0::Constant::create(element::i32, Shape{}, {0});  // sliding_window
 
-    auto cur_seq_len = std::make_shared<v1::Gather>(std::make_shared<v3::ShapeOf>(model->input("input_ids")),
+    auto cur_seq_len = std::make_shared<v8::Gather>(std::make_shared<v3::ShapeOf>(model->input("input_ids")),
                                                     v0::Constant::create(element::i64, Shape{}, {1}),
                                                     v0::Constant::create(element::i64, Shape{}, {0}));
     auto prev_max_seq_len = std::make_shared<v1::Subtract>(max_context_len, cur_seq_len);