Removal of CFLAGS causes packaging/compilation issues with nix-based setups environments

[anshrupani]

Recently, CFLAGS had been removed from the packaging script:
e046621#diff-4ed6d0c254303c7d00c93a8769b017f61a58326b66de29f585e83f91954c54e5L47

I guess this release is consumed by other cpi releases, and therefore, in non-ubuntu based compilation environments, compilation of shared libraries for position independent code is an issue. More details here.