rpi: Install libgomp to target

This is required by imagemagick.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
rpi: Add support for HTTP server

Install an HTTP server with PHP support, but do not start it by default.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>