Enable the 'Hide status bar icons' in Custom restrictions


My project requires to hide the status bar icons and luckily I found the option ‘Hide status bar icons’ in custom restriction (in settings).
But it is grayed out in android pi SDK. I have shared the screenshot below.
I want to enable this option.

device/rockchip/common/device.mk:114:    sys.status.hidebar_enable=false \
device/rockchip/common/device.mk:899:    sys.status.hidebar_enable=false

try modify false to true.

But it does not seem to be working.
‘Hide status bar icons’ is still grayed out. I am not able to enable/disable that option.
Its default value seems to be enabled and it also seems like hardcoded because I was not able to change the status of that tab(Hide status bar icons).

Can anybody suggest a way to enable the “Hide status bar icons” in Custom restrictions?