Building libeXosip2

[Zaki, Ahmed]

Hi,

I am trying to build libeXosip2 but I am running into a problem with SSL.

When I do ./configure then make

I get 

```
make  all-recursive
make[1]: Entering directory '/home/user42/test/libexosip2-5.3.0'
Making all in scripts
make[2]: Entering directory '/home/user42/test/libexosip2-5.3.0/scripts'
make[2]: Nothing to be done for 'all'.
make[2]: Leaving directory '/home/user42/test/libexosip2-5.3.0/scripts'
Making all in platform
make[2]: Entering directory '/home/user42/test/libexosip2-5.3.0/platform'
Making all in vsnet
make[3]: Entering directory '/home/user42/test/libexosip2-5.3.0/platform/vsnet'
make[3]: Nothing to be done for 'all'.
make[3]: Leaving directory '/home/user42/test/libexosip2-5.3.0/platform/vsnet'
make[3]: Entering directory '/home/user42/test/libexosip2-5.3.0/platform'
make[3]: Nothing to be done for 'all-am'.
make[3]: Leaving directory '/home/user42/test/libexosip2-5.3.0/platform'
make[2]: Leaving directory '/home/user42/test/libexosip2-5.3.0/platform'
Making all in src
make[2]: Entering directory '/home/user42/test/libexosip2-5.3.0/src'
make[2]: Nothing to be done for 'all'.
make[2]: Leaving directory '/home/user42/test/libexosip2-5.3.0/src'
Making all in include
make[2]: Entering directory '/home/user42/test/libexosip2-5.3.0/include'
Making all in eXosip2
make[3]: Entering directory '/home/user42/test/libexosip2-5.3.0/include/eXosip2'
make[3]: Nothing to be done for 'all'.
make[3]: Leaving directory '/home/user42/test/libexosip2-5.3.0/include/eXosip2'
make[3]: Entering directory '/home/user42/test/libexosip2-5.3.0/include'
make[3]: Nothing to be done for 'all-am'.
make[3]: Leaving directory '/home/user42/test/libexosip2-5.3.0/include'
make[2]: Leaving directory '/home/user42/test/libexosip2-5.3.0/include'
Making all in tools
make[2]: Entering directory '/home/user42/test/libexosip2-5.3.0/tools'
  CCLD     sip_reg
../src/.libs/libeXosip2.so: undefined reference to `SSL_get_peer_tmp_key’
```
I am have already installed libssl-dev on ubuntu 18.04.5 (using apt-get).

Does libeXosip2 expect a specific version of openssl ?

Thanks
Ahmed