shared: drop stale env-file-label source

env-file-label.[ch] was removed by 3e5320e27d
("env-file: port write_env_file() to label_ops_pre()"), which
replaced write_env_file_label() with WRITE_ENV_FILE_LABEL.

0dc39dffbd ("Use paths specified from environment variables for
/etc configuration files") later reintroduced only
src/shared/env-file-label.c. The header and meson entry were not
restored, no callers use write_env_file_label() or
write_vconsole_conf_label(), and the current write_env_file()
signature no longer matches the stale wrapper.

Remove the unbuilt source file again.

Removed by: 3e5320e27d
Reintroduced by: 0dc39dffbd
Follow-up for: 0dc39dffbd

src/shared/env-file-label.c

@@ -1,36 +0,0 @@
-/* SPDX-License-Identifier: LGPL-2.1-or-later */
-
-#include <sys/stat.h>
-
-#include "env-file.h"
-#include "env-file-label.h"
-#include "locale-setup.h"
-#include "selinux-util.h"
-
-int write_env_file_label(int dir_fd, const char *fname, char **headers, char **l) {
-        int r;
-
-        r = mac_selinux_create_file_prepare(fname, S_IFREG);
-        if (r < 0)
-                return r;
-
-        r = write_env_file(dir_fd, fname, headers, l);
-
-        mac_selinux_create_file_clear();
-
-        return r;
-}
-
-int write_vconsole_conf_label(char **l) {
-        int r;
-
-        r = mac_selinux_create_file_prepare(etc_vconsole_conf(), S_IFREG);
-        if (r < 0)
-                return r;
-
-        r = write_vconsole_conf(AT_FDCWD, etc_vconsole_conf(), l);
-
-        mac_selinux_create_file_clear();
-
-        return r;
-}