Revert "mx6s_capture: switch base addr atomically by DMA completed"

This reverts commit 25d306bd.

this restores the original state of the driver and with is I "sometimes" (need to debug more, when) get "baseaddr switch" errors, but if I get frames, they are always perfectly aligned and nothing is shifting. I'm convinced that this is a needed change. for baseaddr.switch errors see also https://community.nxp.com/t5/i-MX-Processors/Fixing-base-address-switching-Change-Err-which-occurs-randomly/m-p/902311

@dorota.czaplejewicz is this working for you? have you tested this in your trees in the meantime already, by chance?