drivers: base: Print error code on synthetic uevent failure

If we're going to log the failure, we might as well log the return code
too.

Signed-off-by: Brian Norris <briannorris@chromium.org>
Link: https://lore.kernel.org/r/20220824165213.1.Ifdb98af3d0c23708a11d8d5ae5697bdb7e96a3cc@changeid


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>