[1/N] Reorganize multimodal processing code (#32327)

Signed-off-by: DarkLight1337 <tlleungac@connect.ust.hk>

vllm/model_executor/models/pixtral.py

@@ -48,7 +48,8 @@ from vllm.multimodal.inputs import (
     NestedTensors,
 )
 from vllm.multimodal.parse import ImageProcessorItems, ImageSize, MultiModalDataItems
-from vllm.multimodal.processing import (
+from vllm.multimodal.processing import BaseDummyInputsBuilder, ProcessorInputs
+from vllm.multimodal.processing.processor import (
     BaseMultiModalProcessor,
     BaseProcessingInfo,
     MultiModalProcessingInfo,
@@ -56,7 +57,6 @@ from vllm.multimodal.processing import (
     PromptUpdate,
     PromptUpdateDetails,
 )
-from vllm.multimodal.profiling import BaseDummyInputsBuilder, ProcessorInputs
 from vllm.platforms import current_platform
 from vllm.sequence import IntermediateTensors
 from vllm.tokenizers import cached_tokenizer_from_config