Remove ExLlamaV2 backend

- archived upstream: 7dc12af3a8
- replaced by ExLlamaV3, which has much better quantization accuracy

modules/ui.py

@@ -141,7 +141,6 @@ def list_model_elements():
         'compress_pos_emb',
         'compute_dtype',
         'quant_type',
-        'num_experts_per_token',
         'load_in_8bit',
         'load_in_4bit',
         'attn_implementation',
@@ -154,12 +153,8 @@ def list_model_elements():
         'numa',
         'use_double_quant',
         'bf16',
-        'autosplit',
         'enable_tp',
         'tp_backend',
-        'no_flash_attn',
-        'no_xformers',
-        'no_sdpa',
         'cfg_cache',
         'cpp_runner',
         'no_use_fast',