If there is no OFTREE support of_clk_get_by_name failed with
-ENOENT, which caused clk_get to bail out.
This had the effect that nothing was printed on the serial console
with at91sam9263-ek.

There are no error paths that will return -ENODEV as we test for today,
so change this to -ENOENT which is in use.
This allows us to contine with clk_get_sys() in case of other
errors as was the intention of the original fix.

Fixes: 90f7eacb ("clk: let clk_get return errors from of_clk_get_by_name")
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>