Create Debian and RPM packages from CMakeLists

Packages must have a name, a version, a section, an architecture, a maintainer, a description (long and summary), dependencies
Shared libraries must be stripped, have soversion, version (debug symbols are found in separate packages), since MODULE is used instead of SHARED it works as a plugin library which is opened using dlopen-like functionality, see:  https://cmake.org/cmake/help/latest/command/add_library.html
Packages must have postin and postun scripts
Since it is not recommended to modify CMAKE_EXE_LINKER_FLAGS, cmake's path variables are used : https://discourse.cmake.org/t/how-do-i-replace-the-compiler-options-for-one-target/7815/5

.gitignore

@@ -20,6 +20,14 @@ GRTAGS
 GTAGS
 tags
 
+# Package conffiles
+
+tools/packages/oai-lte/conffiles
+tools/packages/oai-nr/conffiles
+tools/packages/liboai-common/conffiles
+tools/packages/liboai-usrp/conffiles
+
+
 # others
 nfapi_nr_interface_scf
 *.log