BugLink: http://bugs.launchpad.net/bugs/1731915

[ Upstream commit 7e9c40c6 ]

In the current boot, clients making use of the AB8500 sysctrl
may be probed before the ab8500-sysctrl driver. This gives them
-EINVAL, but should rather give -EPROBE_DEFER.

Before this, the abx500 clock driver didn't probe properly,
and as a result the codec driver in turn using the clocks did
not probe properly. After this patch, everything probes
properly.

Also add OF compatible-string probing. This driver is all
device tree, so let's just make a drive-by-fix of that as
well.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>