fix maybe-uninitialized errors

Set {listen,server}_sock to -1 when needed as already done in
src/manager.c by commit ecf1fcc845 to
avoid the following build failure:

local.c: In function 'create_and_bind':
local.c:218:12: error: 'listen_sock' may be used uninitialized in this function [-Werror=maybe-uninitialized]
  218 |     return listen_sock;
      |            ^~~~~~~~~~~

Fixes:
 - http://autobuild.buildroot.org/results/27471a878ff52a972ac087d534e44fb0c50808f6

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>

src/local.c

@@ -168,7 +168,7 @@ create_and_bind(const char *addr, const char *port)
 {
     struct addrinfo hints;
     struct addrinfo *result, *rp;
-    int s, listen_sock;
+    int s, listen_sock = -1;
 
     memset(&hints, 0, sizeof(struct addrinfo));
     hints.ai_family   = AF_UNSPEC;   /* Return IPv4 and IPv6 choices */

src/redir.c

@@ -147,7 +147,7 @@ create_and_bind(const char *addr, const char *port)
 {
     struct addrinfo hints;
     struct addrinfo *result, *rp;
-    int s, listen_sock;
+    int s, listen_sock = -1;
 
     memset(&hints, 0, sizeof(struct addrinfo));
     hints.ai_family   = AF_UNSPEC;   /* Return IPv4 and IPv6 choices */

src/server.c

@@ -550,7 +550,7 @@ create_and_bind(const char *host, const char *port, int mptcp)
 {
     struct addrinfo hints;
     struct addrinfo *result, *rp, *ipv4v6bindall;
-    int s, listen_sock;
+    int s, listen_sock = -1;
 
     memset(&hints, 0, sizeof(struct addrinfo));
     hints.ai_family   = AF_UNSPEC;               /* Return IPv4 and IPv6 choices */

src/tunnel.c

@@ -129,7 +129,7 @@ create_and_bind(const char *addr, const char *port)
 {
     struct addrinfo hints;
     struct addrinfo *result, *rp;
-    int s, listen_sock;
+    int s, listen_sock = -1;
 
     memset(&hints, 0, sizeof(struct addrinfo));
     hints.ai_family   = AF_UNSPEC;   /* Return IPv4 and IPv6 choices */

src/udprelay.c

@@ -446,7 +446,7 @@ create_server_socket(const char *host, const char *port)
 {
     struct addrinfo hints;
     struct addrinfo *result, *rp, *ipv4v6bindall;
-    int s, server_sock;
+    int s, server_sock = -1;
 
     memset(&hints, 0, sizeof(struct addrinfo));
     hints.ai_family   = AF_UNSPEC;               /* Return IPv4 and IPv6 choices */