[Bugfix] Make image processor respect mm_processor_kwargs for Qwen2-VL

[li-plus]

Without this PR, if one wants to pass more images with lower resolution to Qwen2-VL models (e.g. 127 images with 256 tokens each):

from vllm import LLM

llm = LLM(
    model="Qwen/Qwen2-VL-7B-Instruct",
    limit_mm_per_prompt={"image": 127},
    mm_processor_kwargs={'max_pixels': 256 * 28 * 28},
)

the LLM instance will be failed to create due to this sequence length check:

vllm/vllm/model_executor/models/qwen2_vl.py

Lines 715 to 719 in e036e52

	if seq_len - max_llm_image_tokens - 2 < 0:
	raise RuntimeError(
	f"Qwen2-VL cannot process {num_images} images in a prompt, "
	"please increase max_model_len or reduce image limit by "
	"--limit-mm-per-prompt.")

because the cached_get_image_processor did not respect mm_processor_kwargs.

This PR fixed this issue and make the above code work.

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[github-actions]

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[DarkLight1337]

Thanks for fixing!