Add more GPU architctures support (#76)

* Add more GPU architctures support

* Merge fmha and mla runner

* add varlen & non varlen support, and add incontiguous tensor support

* update readme

* add varlen api

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Co-authored-by: dianzhangc <dianzhangc@nvidia.com>

flash_mla/__init__.py

@@ -3,4 +3,7 @@ __version__ = "1.0.0"
 from flash_mla.flash_mla_interface import (
     get_mla_metadata,
     flash_mla_with_kvcache,
+    flash_attn_varlen_func,
+    flash_attn_varlen_qkvpacked_func,
+    flash_attn_varlen_kvpacked_func,
 )