rsx: Minor fixes

- vk: Clear dirty textures before copying 'old contents' in case the old data does not fill the new region
- rsx: Properly decode border color - seems to be in BGRA format
- vk: better approximation of border color to better choose between the presets
- vk: Individually clear color images outside render pass and without scissor
- vk: Fix renderpass selection for clear overlay pass
- vk: Include scissor region when emulating clear mask

NOTES:
- vk: Completely avoid using vkClearXXXXimage - its 'broken' on nvidia drivers
  Spec is vague about the function so its not an actual bug
  ClearAttachment is clearly defined as bypassing bound state which works correctly
- TODO: Implement memory sampling to simulate loading precleared memory if cell used memset to preinitialize the framebuffer
  Autoclear depth to 1|255 and color to 0 is hacky!

rpcs3/Emu/RSX/GL/GLGSRender.cpp

@@ -259,7 +259,7 @@ void GLGSRender::end()
 		if (clear_depth)
 		{
 			gl_state.depth_mask(GL_TRUE);
-			gl_state.clear_depth(1.0);
+			gl_state.clear_depth(1.f);
 			gl_state.clear_stencil(255);
 			mask |= GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT;
 		}