[Model] Add PP-OCRv6 Models Support (#45838)
* init
* add pp_plcnetv4 as backbone
* update
* add tests and docs
* update
* fix code style
* update
* remove PP-OCRv6_base_rec since its architecture is the same as small_rec, differing only in config and backbone_config
* remove pp_ocrv6_base_rec doc
* update date
* init det models
* update, add tests and docs
* update
* fix repo
* fix model inits
* fix docs
* add PPOCRV6SmallRecImageProcessor
* fix code style
* fix code style
* update
* nit
* fix
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Co-authored-by: vasqu <antonprogamer@gmail.com>
