libcamera: global_configuration: Drop Option type

The GlobalConfiguration::Option type was introduced to decouple the
configuration option storage from its users, and make changes to the
underlying implementation easier. While the type could indeed be changed
to map to a different class, the API would need to remain the same. The
Option type therefore brings little value. Drop it.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com>
Reviewed-by: Isaac Scott <isaac.scott@ideasonboard.com>

include/libcamera/internal/global_configuration.h

@@ -22,12 +22,10 @@ namespace libcamera {
 class GlobalConfiguration
 {
 public:
-	using Option = const ValueNode &;
-
 	GlobalConfiguration();
 
 	unsigned int version() const;
-	Option configuration() const;
+	const ValueNode &configuration() const;
 
 	template<typename T>
 	std::optional<T> option(