Update comment for vc_dispmanx_resource_read_data
Update comment for vc_dispmanx_resource_read_data

I think this is copying data *from* VideoCore memory, not *to" VideoCore memory.
JamesH65/userland,kraj/userland,6by9/userland,JamesH65/userland,JamesH65/userland,raspberrypi/userland,raspberrypi/userland,kraj/userland,6by9/userland,kraj/userland,6by9/userland,raspberrypi/userland