selftests/bpf: Drop start_server_proto helper

Protocol can be set by __start_server() helper directly now, this makes
the heler start_server_proto() useless.

This patch drops it, and implenments start_server() using make_sockaddr()
and __start_server().
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Link: https://lore.kernel.org/r/55d8a04e0bb8240a5fda2da3e9bdffe6fc8547b2.1714014697.git.tanggeliang@kylinos.cnSigned-off-by: Martin KaFai Lau <martin.lau@kernel.org>

tools/testing/selftests/bpf/network_helpers.c

@@ -120,12 +120,11 @@ static int __start_server(int type, const struct sockaddr *addr, socklen_t addrl
 	return -1;
 }
 
-static int start_server_proto(int family, int type, int protocol,
-			      const char *addr_str, __u16 port, int timeout_ms)
+int start_server(int family, int type, const char *addr_str, __u16 port,
+		 int timeout_ms)
 {
 	struct network_helper_opts opts = {
 		.timeout_ms	= timeout_ms,
-		.proto		= protocol,
 	};
 	struct sockaddr_storage addr;
 	socklen_t addrlen;
@@ -136,12 +135,6 @@ static int start_server_proto(int family, int type, int protocol,
 	return __start_server(type, (struct sockaddr *)&addr, addrlen, false, &opts);
 }
 
-int start_server(int family, int type, const char *addr_str, __u16 port,
-		 int timeout_ms)
-{
-	return start_server_proto(family, type, 0, addr_str, port, timeout_ms);
-}
-
 int *start_reuseport_server(int family, int type, const char *addr_str,
 			    __u16 port, int timeout_ms, unsigned int nr_listens)
 {