socket: downgrade not-supported logging for SO_PASSSEC

Kernel 6.16 started returning EOPNOTSUPP when a required kconfig
is disabled. Downgrade to debug level in that case.

Fixes systemd/systemd#37783

(cherry picked from commit bb887cf)
(cherry picked from commit 42cc4991976821d33b094a4d3787cd6b80a8fbdb)
(cherry picked from commit 1613414ac0a5a370e8754943c273f49ba37edaf3)
(cherry picked from commit b97861d)
(cherry picked from commit 17cccd3)

Author: bluca

src/core/socket.c

@@ -1029,7 +1029,7 @@ static void socket_apply_socket_options(Socket *s, SocketPort *p, int fd) {
         if (s->pass_sec) {
                 r = setsockopt_int(fd, SOL_SOCKET, SO_PASSSEC, true);
                 if (r < 0)
-                        log_unit_warning_errno(UNIT(s), r, "SO_PASSSEC failed: %m");
+                        log_unit_full_errno(UNIT(s), ERRNO_IS_NOT_SUPPORTED(r) ? LOG_DEBUG : LOG_WARNING, r, "SO_PASSSEC failed: %m");
         }
 
         if (s->pass_pktinfo) {

src/journal/journald-native.c

@@ -7,6 +7,7 @@
 #include <unistd.h>
 
 #include "alloc-util.h"
+#include "errno-util.h"
 #include "fd-util.h"
 #include "fs-util.h"
 #include "io-util.h"
@@ -509,7 +510,7 @@ int server_open_native_socket(Server *s, const char *native_socket) {
         if (mac_selinux_use()) {
                 r = setsockopt_int(s->native_fd, SOL_SOCKET, SO_PASSSEC, true);
                 if (r < 0)
-                        log_warning_errno(r, "SO_PASSSEC failed: %m");
+                        log_full_errno(ERRNO_IS_NOT_SUPPORTED(r) ? LOG_DEBUG : LOG_WARNING, r, "SO_PASSSEC failed: %m");
         }
 
         r = setsockopt_int(s->native_fd, SOL_SOCKET, SO_TIMESTAMP, true);

src/journal/journald-syslog.c

@@ -7,6 +7,7 @@
 #include "sd-messages.h"
 
 #include "alloc-util.h"
+#include "errno-util.h"
 #include "fd-util.h"
 #include "format-util.h"
 #include "io-util.h"
@@ -492,7 +493,7 @@ int server_open_syslog_socket(Server *s, const char *syslog_socket) {
         if (mac_selinux_use()) {
                 r = setsockopt_int(s->syslog_fd, SOL_SOCKET, SO_PASSSEC, true);
                 if (r < 0)
-                        log_warning_errno(r, "SO_PASSSEC failed: %m");
+                        log_full_errno(ERRNO_IS_NOT_SUPPORTED(r) ? LOG_DEBUG : LOG_WARNING, r, "SO_PASSSEC failed: %m");
         }
 
         r = setsockopt_int(s->syslog_fd, SOL_SOCKET, SO_TIMESTAMP, true);