Assume that exit() does not throw or requires a proxy

Author: kleisauke

src/library_syscall.js

@@ -1216,6 +1216,8 @@ var SyscallsLibrary = {
 #if MINIMAL_RUNTIME
   __sys_exit_group__deps: ['$exit'],
 #endif
+  __sys_exit_group__nothrow: true,
+  __sys_exit_group__proxy: false,
   __sys_exit_group: function(status) {
     exit(status);
     return 0;