Conv2D direct support (#744)

* Conv2DDirect for VAE stage

* Enable only for Vulkan, reduced duplicated code

* Cmake option to use conv2d direct

* conv2d direct always on for opencl

* conv direct as a flag

* fix merge typo

* Align conv2d behavior to flash attention's

* fix readme

* add conv2d direct for controlnet

* add conv2d direct for esrgan

* clean code, use enable_conv2d_direct/get_all_blocks

* format code

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Co-authored-by: leejet <leejet714@gmail.com>

README.md

@@ -341,6 +341,10 @@ arguments:
   --diffusion-fa                     use flash attention in the diffusion model (for low vram)
                                      Might lower quality, since it implies converting k and v to f16.
                                      This might crash if it is not supported by the backend.
+  --diffusion-conv-direct            use Conv2d direct in the diffusion model
+                                     This might crash if it is not supported by the backend.
+  --vae-conv-direct                  use Conv2d direct in the vae model (should improve the performance)
+                                     This might crash if it is not supported by the backend.
   --control-net-cpu                  keep controlnet in cpu (for low vram)
   --canny                            apply canny preprocessor (edge detection)
   --color                            colors the logging tags according to level