D57497 added -msmall-data-limit= as an alias for -G and defaulted it to 8 for
GCC documents this option as "Put global and static data smaller than <number> bytes into a special section (on some targets)."
The targets are not documented, but it seems to not use the value for -fpie.
I think the different behavior for -fno-pic/-fpie/-fpic is not a good
idea and defaulting to -msmall-data-limit=0 makes more sense.