Fix read_uhdm frontend
Fix read_uhdm frontend

extra_args is neccessary for read_uhdm frontend as it sets filename

Signed-off-by: Kamil Rakoczy <539d6a2650324aa9156edbbb09228193dfee5b9b@antmicro.com>

chipsalliance/yosys-f4pga-plugins,chipsalliance/yosys-f4pga-plugins