Simple USB cameras do not work (fix proposed )

[sletteland]

Hello ZM dev team

simple/primitive USB cameras ( for example using the gspsa driver ) do not work properly with ZoneMinder (zmc keeps crashing )

for example : 0c45:6005 Microdia Sweex Mini Webcam ,

I propose a fix for that (patch against zm 37.40 / master dev )
This uses libv4l2 (https://github.com/philips/libv4l) for local USB cameras .

This allows very simple/primitive cameras to work out of the box .
(like for example USB cameras using the gspca driver )

A pull Request has just been made (sletteland/zoneminder branch libv4l2 )