HLE: Use a member variable instead of a virtual function to retrieve the max number of sessions that can be connected to an HLE service at the same time.

src/core/hle/service/apt/apt.h

@@ -14,6 +14,8 @@ class Interface;
 
 namespace APT {
 
+static const u32 MaxAPTSessions = 2; ///< Each APT service can only have up to 2 sessions connected at the same time.
+
 /// Holds information about the parameters used in Send/Glance/ReceiveParameter
 struct MessageParameter {
     u32 sender_id = 0;

src/core/hle/service/apt/apt_a.cpp

@@ -39,7 +39,7 @@ const Interface::FunctionInfo FunctionTable[] = {
     {0x01020000, CheckNew3DS, "CheckNew3DS"},
 };
 
-APT_A_Interface::APT_A_Interface() {
+APT_A_Interface::APT_A_Interface() : Interface(MaxAPTSessions) {
     Register(FunctionTable);
 }
 

src/core/hle/service/apt/apt_s.cpp

@@ -99,7 +99,7 @@ const Interface::FunctionInfo FunctionTable[] = {
     {0x01020000, CheckNew3DS, "CheckNew3DS"},
 };
 
-APT_S_Interface::APT_S_Interface() {
+APT_S_Interface::APT_S_Interface() : Interface(MaxAPTSessions) {
     Register(FunctionTable);
 }
 

src/core/hle/service/apt/apt_u.cpp

@@ -99,7 +99,7 @@ const Interface::FunctionInfo FunctionTable[] = {
     {0x01020000, CheckNew3DS, "CheckNew3DS"},
 };
 
-APT_U_Interface::APT_U_Interface() {
+APT_U_Interface::APT_U_Interface() : Interface(MaxAPTSessions) {
     Register(FunctionTable);
 }