Fix modules/ typos

Found using `codespell -q 3 -S ./3rdparty -L activ,amin,ang,atleast,childs,dof,endwhile,halfs,hist,iff,nd,od,uint`

backporting of commit: ec43292e1e

modules/highgui/src/window_gtk.cpp

@@ -1806,7 +1806,7 @@ static gboolean icvOnMouse( GtkWidget *widget, GdkEvent *event, gpointer user_da
     else if( event->type == GDK_SCROLL )
     {
 #if defined(GTK_VERSION3_4)
-        // NOTE: in current implementation doesn't possible to put into callback function delta_x and delta_y separetely
+        // NOTE: in current implementation doesn't possible to put into callback function delta_x and delta_y separately
         double delta = (event->scroll.delta_x + event->scroll.delta_y);
         cv_event   = (event->scroll.delta_y!=0) ? CV_EVENT_MOUSEHWHEEL : CV_EVENT_MOUSEWHEEL;
 #else

modules/highgui/src/window_w32.cpp

@@ -1219,7 +1219,7 @@ cvShowImage( const char* name, const CvArr* arr )
                      dst_ptr, (size.cx * channels + 3) & -4 );
     cvConvertImage( image, &dst, origin == 0 ? CV_CVTIMG_FLIP : 0 );
 
-    // ony resize window if needed
+    // only resize window if needed
     if (changed_size)
         icvUpdateWindowPos(window);
     InvalidateRect(window->hwnd, 0, 0);