Patch: Declare some undeclared TLS functions (ITS#1708)

[h.b.furuseth@usit.uio.no]

Full_Name: Hallvard B. Furuseth
Version: 2.1.0alpha
OS: Linux
URL: http://folk.uio.no/hbf/OpenLDAP/undeclared.txt
Submission from: (NULL) (158.36.148.34)


This patch declares some functions that are used but not declared.

ldap_pvt_tls_sb_ctx() is the most important one, since it does not
return int.  Casting the return type back to void*, like the code does
now, only works if int and void* have the same size and casting doesn't
change the value.