thanks to Supreeth Herle for reporting.

clang have changed its default standard to C11 compilation and is stricter.
Ensure use of gnu89 standard to use pthread extension for --castxml-gccxml

It can't link because nas_config.c and rb_config.c was commented.

The unit simulators may still need some checks.

plus some cleanup here and there

The T only works when it's TRUE, the version without shared memory
is not supported anymore.

added lte-enb.c which extracts all enb-specific code from lte-softmodem. corrects merge from develop branch in dlsch_modulations.c. removal of HW-specific code in lte-softmodem.c

probably not be here.

Also modified CMakeLists.txt to run asn1tostruct.py at cmake time,
because the generated Makefile was wrong. When compiling with -j4
it would mess up by calling fix_asn1 twice with a weird timing,
leading to failures.