soc: amlogic: meson-ee-pwrc: propagate PD provider registration errors

soc: amlogic: meson-ee-pwrc: propagate PD provider registration errors

BugLink: https://bugs.launchpad.net/bugs/1861090
commit 0766d65e6afaea8b80205a468207de9f18cd7ec8 upstream.

of_genpd_add_provider_onecell() can return an error. Propagate the error
so the driver registration fails when of_genpd_add_provider_onecell()
did not work.

Fixes: eef3c2ba0a42a6 ("soc: amlogic: Add support for Everything-Else power domains controller")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>