zbarcam: add page (#10459)

* zbarcam: add page

---------

Co-authored-by: pixel <pixel+github@chrissx.de>

pages/linux/zbarcam.md

@@ -0,0 +1,20 @@
+# zbarcam
+
+> Scans and decodes barcodes (and QR codes) from a video device.
+> More information: <https://manned.org/zbarcam>.
+
+- Continuously read barcodes and print them to standard output:
+
+`zbarcam`
+
+- Disable output video window while scanning:
+
+`zbarcam --nodisplay`
+
+- Print barcodes without type information:
+
+`zbarcam --raw`
+
+- Define capture device:
+
+`zbarcam /dev/{{video_device}}`