Add Mutipath TCP (MPTCP) support

MPTCP is a TCP extension allowing to improve network reliabilty by using mutiple network interface for the same TCP connection. Check https://www.mptcp.dev and https://developer.apple.com/documentation/foundation/urlsessionconfiguration/improving_network_reliability_using_multipath_tcp for details. Changes to this repository include declaring a new sharedMPTCPSession property in NSURLSession, and replacing previous uses of [NSURLSession sharedSession] to [NSURLSession sharedMPTCPSession]

Link to GitHub: https://github.com/videolan/vlc-ios/pull/457

Resources/iOS/VLC.entitlements

@@ -18,6 +18,8 @@
 	</array>
 	<key>com.apple.developer.networking.multicast</key>
 	<true/>
+	<key>com.apple.developer.networking.multipath</key>
+	<true/>
 	<key>com.apple.developer.siri</key>
 	<true/>
 	<key>com.apple.developer.ubiquity-container-identifiers</key>