tls: work-in-progress TLS1.2 test applet

tls: work-in-progress TLS1.2 test applet

function                                             old     new   delta
tls_main                                               -     733    +733
dump                                                   -     230    +230
xread_tls_block                                        -     180    +180
get_der_len                                            -      76     +76
enter_der_item                                         -      70     +70
skip_der_item                                          -      56     +56
get24be                                                -      24     +24
tls_error_die                                          -      19     +19
packed_usage                                       31010   31027     +17
applet_names                                        2549    2553      +4
applet_main                                         1472    1476      +4
applet_suid                                           92      93      +1
applet_install_loc                                   184     185      +1
------------------------------------------------------------------------------
(add/remove: 9/0 grow/shrink: 5/0 up/down: 1415/0)           Total: 1415 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>