openpli.conf: add 'madwifi' in the DISTRO_FEATURES
openpli.conf: add 'madwifi' in the DISTRO_FEATURES

This allows machines to enable madwifi by adding 'pci' in
their MACHINE_FEATURES

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