mv_barcode: Export zint symbol

mv_barcode: Export zint symbol

barcode_generate_{source,image} had a common code but was separated
into completely different codes generateBarcode{ToImage, Mat}.
Also zint symbol copied to mv_source or opencv mat multiple time,
it wasted performance. So just export one symbol and use it

Diagram is,
zint_symbol -> mv_source = mv_barcode_gen_source
            \> opencv mat -> post processing = mv_barcode_gen_image

Needs to merge BarcodeGenerator.h and mv_barcode_generate_open.h later

Change-Id: Ie77a3befd01324ecbc6890f0cda3d33845360678
Signed-off-by: Kwanghoon Son <k.son@samsung.com>