BUILD: ssl: guard SSL_CTX_add_server_custom_ext with special macro

special guard macros HAVE_SSL_CTX_ADD_SERVER_CUSTOM_EXT was defined earlier
exactly for guarding SSL_CTX_add_server_custom_ext, let us use it wherever
appropriate

(cherry picked from commit f00cdb18563e6f57a4ad6c0b40e0116ca9c8fd69)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
1 file changed