[noPoll] Compile error deprecated functions TLS

[Chris Severance]

https://aur.archlinux.org/packages/nopoll/
% gcc --version
gcc (GCC) 7.1.1 20170528
% pacman -Q openssl
openssl 1.1.0.f-1

nopoll_conn.c:586:3: error: 'TLSv1_client_method' is deprecated
[-Werror=deprecated-declarations]
nopoll_conn.c:586:3: error: 'TLSv1_server_method' is deprecated
[-Werror=deprecated-declarations]
nopoll_conn.c:615:3: error: 'TLSv1_client_method' is deprecated
[-Werror=deprecated-declarations]
nopoll_conn.c:615:3: error: 'TLSv1_server_method' is deprecated
[-Werror=deprecated-declarations]
nopoll_conn.c:620:3: error: 'TLSv1_1_client_method' is deprecated
[-Werror=deprecated-declarations]
nopoll_conn.c:620:3: error: 'TLSv1_1_server_method' is deprecated
[-Werror=deprecated-declarations]
nopoll_conn.c:625:3: error: 'TLSv1_2_client_method' is deprecated
[-Werror=deprecated-declarations]
nopoll_conn.c:625:3: error: 'TLSv1_2_server_method' is deprecated
[-Werror=deprecated-declarations]
nopoll_conn.c:642:2: error: 'TLSv1_client_method' is deprecated
[-Werror=deprecated-declarations]
nopoll_conn.c:642:2: error: 'TLSv1_server_method' is deprecated
[-Werror=deprecated-declarations]
nopoll_conn.c:2478:18: error: storage size of 'mdctx' isn't known
nopoll_conn.c:2478:18: error: unused variable 'mdctx'
[-Werror=unused-variable]