fsogsmd: const: add networkSignalIndicatorToPercentage()
fsogsmd: const: add networkSignalIndicatorToPercentage()

slyon/debian-libfsoframework,slyon/debian-libfsoframework,slyon/debian-fso-usaged,slyon/debian-fso-deviced,slyon/debian-fso-usaged,slyon/debian-fso-deviced