[macOS] don't fail if macdeployqt is missing

- it's needed only at install time (when creating dmg)
- ConanCenter binaries don't have it

osx/CMakeLists.txt

@@ -9,9 +9,8 @@ if(APPLE_MACOS)
 		if(CMAKE_HOST_SYSTEM_PROCESSOR STREQUAL CMAKE_SYSTEM_PROCESSOR)
 			# deploy Qt dylibs with macdeployqt
 			find_program(TOOL_MACDEPLOYQT NAMES macdeployqt PATHS ${qt_base_dir}/bin)
-			if(NOT TOOL_MACDEPLOYQT)
-				message(FATAL_ERROR "Could not find macdeployqt")
-			endif()
+		endif()
+		if(TOOL_MACDEPLOYQT)
 			install(CODE "
 				execute_process(COMMAND
 					\"${TOOL_MACDEPLOYQT}\" \"${bundleDir}\" -verbose=2