Local logins freeze the server.

[Yann Kaiser]

To reproduce:
1/ Compile arma with pthreads and authentication support
2/ Start a server
3/ GLOBAL_ID 1 on the console (also TRUST_LAN 1 if needed)
4/ Connect with a client (log out if needed)
5/ Type /login someone@
6/ Watch it freeze

Backtrace:
#0 0xb8005424 in __kernel_vsyscall ()
#1 0xb7fd56c9 in __lll_lock_wait () from /lib/libpthread.so.0
#2 0xb7fd0c26 in _L_lock_58 () from /lib/libpthread.so.0
#3 0xb7fd0532 in pthread_mutex_lock () from /lib/libpthread.so.0
#4 0x081739ee in st_ToDo ()
#5 0x08113fea in nLoginProcess::FetchInfoFromAuthority ()
#6 0x08114efd in nMemberFunctionRunnerTemplate<nLoginProcess>::FinishAll ()
#7 0x08173ac2 in st_DoToDo ()
#8 0x0806b5df in sg_EnterGameCore ()
#9 0x0806b6a4 in sg_EnterGame ()
#10 0x0806c787 in own_game ()
#11 0x08072e70 in sg_HostGame ()
#12 0x0804df8d in main ()

Workaround:
 * Disable pthreads support in favor of zthread support