There is no real need for a function template. It is not defined in a
header file, so it has limited availability, and there exists only a
single instantion.
So convert it to use `std::ostream` directly, like most `operator<<`
in the code base.
Signed-off-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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