devel/libgpr: Rename to libgnatprj.so to avoid conflict

[saper_saper.info]

Summary

• libgpr.so is likely to conflict with gRPC library
• set SONAME and the major version
• verbose build and installation

Patches obtained from the Fedora project

[saper_saper.info]

devel/libgpr/files/gprbuild-usrmove.patch

8

I think this is not necessary for FreeBSD - this file got committed by accident, it is also not taken into account by make patch.

Let's remove this file altogether before (and if) we commit this.