Add TRTSplitter (#64762)

Add TRTSplitter (#64762)

Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/64762

Extract and format TRTSplitter from fx2trt_example code, current implementation is tentative, subject to changed based on feeds model lowering progress.

Test Plan:
manul print of supported operator:
`{<class 'torch.nn.modules.activation.ReLU'>: None, <function relu at 0x7f9b1abd0790>: None, <class 'torch.nn.modules.activation.Sigmoid'>: None, <class 'torch.nn.modules.pooling.AdaptiveAvgPool2d'>: None, <built-in method add of type object at 0x7f9b7f402498>: None, <built-in function add>: None, <built-in method add of PyCapsule object at 0x7f9b1a3dc690>: None, <built-in method add_relu of PyCapsule object at 0x7f9b1a34cf90>: None, <class 'torch.nn.modules.batchnorm.BatchNorm2d'>: None, <class 'torch.nn.quantized.modules.batchnorm.BatchNorm2d'>: None, <class 'torch.nn.modules.conv.Conv2d'>: None, <class 'torch.nn.quantized.modules.conv.Conv2d'>: None, <class 'torch.nn.intrinsic.quantized.modules.conv_relu.ConvReLU2d'>: None, <class 'torch.nn.modules.linear.Linear'>: None, <class 'torch.nn.quantized.modules.linear.Linear'>: None, <class 'torch.nn.modules.pooling.MaxPool2d'>: None, <built-in function mul>: None, <built-in method mul of type object at 0x7f9b7f402498>: None, <built-in method mul of PyCapsule object at 0x7f9b1a3dc6c0>: None, <built-in method flatten of type object at 0x7f9b7f402498>: None, <class 'torch.nn.quantized.modules.DeQuantize'>: None, <built-in method dequantize of type object at 0x7f9b7f402498>: None, 'dequantize': None, <class 'torch.nn.quantized.modules.Quantize'>: None, <built-in method quantize_per_tensor of type object at 0x7f9b7f402498>: None, <class 'torch.nn.modules.linear.Identity'>: None, <function conv2d at 0x7f9b1a1fe9d0>: None, <function flatten at 0x7f9b1a1f5ca0>: None, <function size at 0x7f9b1a1f5b80>: None, <function batch_norm at 0x7f9b1a1feaf0>: None, <function layer_norm at 0x7f9b1a1feb80>: None, <function softmax at 0x7f9b1a1f9550>: None, <function relu at 0x7f9b1a1fe040>: None, <function sin at 0x7f9b1a2030d0>: None, <function cos at 0x7f9b1a203160>: None, <function tan at 0x7f9b1a2031f0>: None, <function sinh at 0x7f9b1a1fe160>: None, <function cosh at 0x7f9b1a1fe280>: None, <function tanh at 0x7f9b1a1fe310>: None, <function asin at 0x7f9b1a1fe3a0>: None, <function acos at 0x7f9b1a1fe430>: None, <function atan at 0x7f9b1a1fe4c0>: None, <function exp at 0x7f9b1a1fe550>: None, <function log at 0x7f9b1a1fe5e0>: None, <function sqrt at 0x7f9b1a1fe670>: None, <function reciprocal at 0x7f9b1a1fe700>: None, <function abs at 0x7f9b1a1fe790>: None, <function neg at 0x7f9b1a1fe820>: None, <function floor at 0x7f9b1a1fe8b0>: None, <function ceil at 0x7f9b1a1fe940>: None, <function sum at 0x7f9b1a1f9c10>: None, <function max_pool2d at 0x7f9b1a1f5d30>: None, <function squeeze at 0x7f9b1a1f5c10>: None, <function add at 0x7f9b1a1f91f0>: None, <function sub at 0x7f9b1a1f9ca0>: None, <function div at 0x7f9b1a1f9dc0>: None, <function mul at 0x7f9b1a1f9d30>: None, <function pow at 0x7f9b1a1f9e50>: None, <function min_two_tensors_input at 0x7f9b1a1f9940>: None, <function unsqueeze at 0x7f9b1a1f9280>: None, <function topk at 0x7f9b1a203280>: None, <function adaptive_avg_pool2d at 0x7f9b1a1f5dc0>: None, <function avg_pool2d at 0x7f9b1a1f5e50>: None, <function reshape at 0x7f9b1a203550>: None, <function slice_tensor at 0x7f9b1a1fee50>: None, <function split at 0x7f9b1a1fec10>: None, <function linear at 0x7f9b1a1f51f0>: None, <function clamp at 0x7f9b1a1f93a0>: None, <function tuple_construct at 0x7f9b1a1fed30>: None, <function contiguous at 0x7f9b1a1f9430>: None, <function getitem at 0x7f9b1a203310>: None, <function cat at 0x7f9b1a1f9310>: None, <function transpose at 0x7f9b1a1f94c0>: None, <function matmul at 0x7f9b1a1f98b0>: None, <function sigmoid at 0x7f9b1a1fe1f0>: None, <function permute at 0x7f9b1a1f9670>: None, <function quantize_per_tensor at 0x7f9b1a1f9b80>: None, <function dequantize at 0x7f9b1a1f99d0>: None, <function sign at 0x7f9b1a1f5ee0>: None}`

Reviewed By: 842974287

Differential Revision: D30798047

fbshipit-source-id: 69076a550874425b7186fbbf2ecf03da4a99b42f