c52e8cde3e
std::visit() allows quite elegant type-matching implementation of the visitor pattern. The 'overloaded' type helpers allow to define a hierarchy of overloaded operator() implementations which can be used by std::visit(). Currently only the Virtual pipeline handler uses this type-matching implementation of std::visit(). To prepare to add another user in the Mali C55 pipeline handler move the 'overloaded' helper type to libcamera::utils for easier re-use. Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com> Reviewed-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>