[hid_core] fix LM2 crash due to callbacks not being removed properly (#4178)

the function returned the key AFTER this one, which points to an invalid object
basically its like "oh im returning the index AFTER Myself"
off-by-1 error basically; now it returns OUR own key.

Signed-off-by: lizzie <lizzie@eden-emu.dev>

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/4178
Reviewed-by: MaranBr <maranbr@eden-emu.dev>
Reviewed-by: CamilleLaVey <camillelavey99@gmail.com>

src/core/core.cpp

@@ -108,7 +108,7 @@ FileSys::VirtualFile GetGameFileFromPath(const FileSys::VirtualFilesystem& vfs,
 
 struct System::Impl {
     explicit Impl(System& system)
-        : kernel{system}, fs_controller{system}, hid_core{system.Kernel()}, cpu_manager{system},
+        : kernel{system}, fs_controller{system}, hid_core{kernel}, cpu_manager{system},
           reporter{system}, applet_manager{system}, frontend_applets{system}, profile_manager{} {}
 
     u64 program_id;