lxc: Fix coverity findings

Error: UNINIT:
/libvirt/src/lxc/lxc_driver.c:1412:
var_decl: Declaring variable "fd" without initializer.
/libvirt/src/lxc/lxc_driver.c:1460:
uninit_use_in_call: Using uninitialized value "fd" when calling "virFileClose".
/libvirt/src/util/virfile.c:50:
read_parm: Reading a parameter value.

Error: DEADCODE:
/libvirt/src/lxc/lxc_controller.c:960:
dead_error_condition: On this path, the condition "ret == 4" cannot be true.
/libvirt/src/lxc/lxc_controller.c:959:
at_most: After this line, the value of "ret" is at most -1.
/libvirt/src/lxc/lxc_controller.c:959:
new_values: Noticing condition "ret < 0".
/libvirt/src/lxc/lxc_controller.c:961:
dead_error_line: Execution cannot reach this statement "continue;".

Error: UNINIT:
/libvirt/src/lxc/lxc_controller.c:1104:
var_decl: Declaring variable "consoles" without initializer.
/libvirt/src/lxc/lxc_controller.c:1237:
uninit_use: Using uninitialized value "consoles".

(cherry picked from commit f74471de4f)

src/lxc/lxc_controller.c

@@ -957,7 +957,7 @@ static void lxcEpollIO(int watch, int fd, int events, void *opaque)
         int ret;
         ret = epoll_wait(console->epollFd, &event, 1, 0);
         if (ret < 0) {
-            if (ret == EINTR)
+            if (errno == EINTR)
                 continue;
             virReportSystemError(errno, "%s",
                                  _("Unable to wait on epoll"));
@@ -1101,7 +1101,7 @@ static int lxcControllerMain(int serverFd,
                              size_t nFds,
                              pid_t container)
 {
-    struct lxcConsole *consoles;
+    struct lxcConsole *consoles = NULL;
     struct lxcMonitor monitor = {
         .serverFd = serverFd,
         .clientFd = clientFd,

src/lxc/lxc_driver.c

@@ -1409,7 +1409,7 @@ static int lxcMonitorClient(lxc_driver_t * driver,
                             virDomainObjPtr vm)
 {
     char *sockpath = NULL;
-    int fd;
+    int fd = -1;
     struct sockaddr_un addr;
 
     if (virAsprintf(&sockpath, "%s/%s.sock",