block: Ignore close() failure in get_tmp_filename()

The temporary file has been created and is ready for use. Checking
return value of close() does not seem useful. The file descriptor
is almost certainly closed; see close(2) under "Dealing with error
returns from close()".

Let's simply ignore close() failure here.

Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221010040432.3380478-1-bin.meng@windriver.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block.c

@@ -887,10 +887,7 @@ int get_tmp_filename(char *filename, int size)
     if (fd < 0) {
         return -errno;
     }
-    if (close(fd) != 0) {
-        unlink(filename);
-        return -errno;
-    }
+    close(fd);
     return 0;
 #endif
 }