[sgl-kernel] support hadamard (#11663)

sgl-kernel/python/sgl_kernel/__init__.py

@@ -270,6 +270,13 @@ from sgl_kernel.gemm import (
     silu_and_mul_scaled_fp4_grouped_quant,
 )
 from sgl_kernel.grammar import apply_token_bitmask_inplace_cuda
+from sgl_kernel.hadamard import (
+    hadamard_transform,
+    hadamard_transform_12n,
+    hadamard_transform_20n,
+    hadamard_transform_28n,
+    hadamard_transform_40n,
+)
 from sgl_kernel.kvcacheio import (
     transfer_kv_all_layer,
     transfer_kv_all_layer_mla,