inline 'using Fn = std::function<Signature>;' to fix the build
.../Telegram/SourceFiles/platform/linux/current_geo_location_linux.cpp:121:7: error: alias template 'Fn' requires template arguments; argument deduction only allowed for class templates

Index: Telegram/SourceFiles/platform/linux/current_geo_location_linux.cpp
--- Telegram/SourceFiles/platform/linux/current_geo_location_linux.cpp.orig
+++ Telegram/SourceFiles/platform/linux/current_geo_location_linux.cpp
@@ -118,7 +118,7 @@ void ResolveCurrentExactLocation(Fn<void(Core::GeoLoca
 				.accuracy = Core::GeoLocationAccuracy::Exact,
 			});
 		}),
-		new Fn(callback));
+		new std::function(callback));
 }
 
 void ResolveLocationAddress(
@@ -193,7 +193,7 @@ void ResolveLocationAddress(
 
 			(*callback)({ .name = checked.join(u", "_q) });
 		}),
-		new Fn(callback));
+		new std::function(callback));
 }
 
 } // namespace Platform
