regulator: rt5133: Fix IS_ERR() vs NULL bug in rt5133_validate_vendor_info()

The "priv->cdata" pointer isn't an error pointer; this should be a NULL
check instead.  Otherwise it leads to a NULL pointer dereference in the
caller, rt5133_probe().

Fixes: 714165e1 ("regulator: rt5133: Add RT5133 PMIC regulator Support")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://patch.msgid.link/aKMc1oK-7yY4cD3K@stanley.mountain


Signed-off-by: Mark Brown <broonie@kernel.org>