### What this PR does / why we need it? It fixes following bugs: 1. When searching a specific linear quantization implementation from a tool (such as MindIE-Turbo), the mapping of packed linear is required to identify correponding quant type. 2. The exception is narrowed down to ImportError when importing MindIETurboQuantizer to better throw other errors. 3. The api of AscendKVCacheMethod.apply is aligned with that in AscendAttentionBackendImpl. ### Does this PR introduce _any_ user-facing change? No ### How was this patch tested? By performing offline inference:  --------- Signed-off-by: angazenn <zengyanjia@huawei.com> Co-authored-by: angazenn <zengyanjia@huawei.com>