Clean up API & Bypass torch.autograd.Function (#30)

Signed-off-by: Woosuk Kwon <woosuk.kwon@berkeley.edu>

vllm_flash_attn/__init__.py

@@ -3,10 +3,6 @@ __version__ = "2.6.2"
 # Use relative import to support build-from-source installation in vLLM
 from .flash_attn_interface import (
     flash_attn_func,
-    flash_attn_kvpacked_func,
-    flash_attn_qkvpacked_func,
     flash_attn_varlen_func,
-    flash_attn_varlen_kvpacked_func,
-    flash_attn_varlen_qkvpacked_func,
     flash_attn_with_kvcache,
 )