[#2605] Update to PJSIP 1.5.5

...ne-common/libs/pjproject/pjlib/include/pj/compat/string.h

sflphone-common/libs/pjproject/pjlib/include/pj/config.h

...hone-common/libs/pjproject/pjlib/include/pj/config_site.h

sflphone-common/libs/pjproject/pjlib/include/pj/errno.h

sflphone-common/libs/pjproject/pjlib/include/pj/sock.h

sflphone-common/libs/pjproject/pjlib/include/pj/sock_qos.h

sflphone-common/libs/pjproject/pjlib/include/pj/ssl_sock.h

sflphone-common/libs/pjproject/pjlib/include/pj/timer.h

sflphone-common/libs/pjproject/pjlib/include/pjlib.h

sflphone-common/libs/pjproject/pjlib/src/pj/activesock.c

...one-common/libs/pjproject/pjlib/src/pj/addr_resolv_sock.c

...ommon/libs/pjproject/pjlib/src/pj/addr_resolv_symbian.cpp

sflphone-common/libs/pjproject/pjlib/src/pj/config.c

sflphone-common/libs/pjproject/pjlib/src/pj/errno.c

...-common/libs/pjproject/pjlib/src/pj/exception_symbian.cpp

...ne-common/libs/pjproject/pjlib/src/pj/ioqueue_symbian.cpp

sflphone-common/libs/pjproject/pjlib/src/pj/ioqueue_winnt.c

...ne-common/libs/pjproject/pjlib/src/pj/ip_helper_generic.c

...-common/libs/pjproject/pjlib/src/pj/ip_helper_symbian.cpp

...hone-common/libs/pjproject/pjlib/src/pj/ip_helper_win32.c