openpli-enigma2-image: add rt73-firmware to the image
openpli-enigma2-image: add rt73-firmware to the image

BlackPole/bp-openembedded,nx111/openembeded_openpli2.1_nx111,SIFTeam/openembedded,SIFTeam/openembedded,BlackPole/bp-openembedded,BlackPole/bp-openembedded,nx111/openembeded_openpli2.1_nx111,nx111/openembeded_openpli2.1_nx111,nx111/openembeded_openpli2.1_nx111,BlackPole/bp-openembedded,BlackPole/bp-openembedded,BlackPole/bp-openembedded,nx111/openembeded_openpli2.1_nx111,BlackPole/bp-openembedded,nx111/openembeded_openpli2.1_nx111,SIFTeam/openembedded,SIFTeam/openembedded,nx111/openembeded_openpli2.1_nx111,SIFTeam/openembedded,SIFTeam/openembedded,SIFTeam/openembedded,nx111/openembeded_openpli2.1_nx111