test: span: Use intended variable

It appears that the original intention was to use it in these
particular constructor tests: the variable is otherwise unused,
and `Span<const int>{ v }` is already tested.

Signed-off-by: Barnabás Pőcze <pobrn@protonmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

test/span.cpp

@@ -143,9 +143,9 @@ protected:
 		Span<const int>{ v };
 		/* Span<float>{ v }; */
 
-		Span<const int>{ v };
-		/* Span<int>{ v }; */
-		/* Span<const float>{ v }; */
+		Span<const int>{ cv };
+		/* Span<int>{ cv }; */
+		/* Span<const float>{ cv }; */
 
 		Span<int> dynamicSpan{ i };
 		Span<int>{ dynamicSpan };