VideoCommon: drop UpdateViewportWithCorrection

It's only used once in BPFunction which itself is also only used once.
So the setter is moved to BPStructs like all other ones.

Source/Core/VideoCommon/Src/BPFunctions.cpp

@@ -49,8 +49,6 @@ void SetScissor()
 
 	TargetRectangle trc = g_renderer->ConvertEFBRectangle(rc);
 	g_renderer->SetScissorRect(trc);
-
-	UpdateViewportWithCorrection();
 }
 
 void SetLineWidth()

Source/Core/VideoCommon/Src/BPStructs.cpp

@@ -185,6 +185,7 @@ void BPWritten(const BPCmd& bp)
 	case BPMEM_SCISSORBR: // Scissor Rectable Bottom, Right
 	case BPMEM_SCISSOROFFSET: // Scissor Offset
 		SetScissor();
+		VertexShaderManager::SetViewportChanged();
 		break;
 	case BPMEM_LINEPTWIDTH: // Line Width
 		SetLineWidth();

Source/Core/VideoCommon/Src/VertexShaderManager.cpp

@@ -175,13 +175,6 @@ static void ViewportCorrectionMatrix(Matrix44& result)
 
 void UpdateViewport();
 
-void UpdateViewportWithCorrection()
-{
-	// TODO: get rid of this function
-	ViewportCorrectionMatrix(s_viewportCorrection);
-	UpdateViewport();
-}
-
 void VertexShaderManager::Init()
 {
 	Dirty();

Source/Core/VideoCommon/Src/VertexShaderManager.h

@@ -12,8 +12,6 @@ class PointerWrap;
 
 void UpdateProjectionHack(int iParams[], std::string sParams[]);
 
-void UpdateViewportWithCorrection();
-
 // The non-API dependent parts.
 class VertexShaderManager
 {