BUILD/MINOR: ssl: fix compiler warning about useless statement

There is a compiler warning after commit a9363eb6 ("BUG/MEDIUM: ssl:
'tune.ssl.default-dh-param' value ignored with openssl > 1.1.1"):

src/ssl_sock.c: In function 'ssl_sock_prepare_ctx':
src/ssl_sock.c:4481:4: error: statement with no effect [-Werror=unused-value]

Fix it by adding a (void)

(cherry picked from commit 3c8bde88ca0c189536db741ab6f6de0b4a4fe15d)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
1 file changed