of: property: Remove unneeded return variable

This patch removes unneeded return variables, using only
'0' instead.
It fixes the following warning detected by coccinelle:
./drivers/of/property.c:1371:5-8: Unneeded variable: "ret". Return "0"
on line 1388

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Link: https://lore.kernel.org/r/1614676598-105267-1-git-send-email-yang.lee@linux.alibaba.com


Signed-off-by: Rob Herring <robh@kernel.org>