Add compression support in EGPRS PUAN

This adds compression of bitmap in PUAN. The compressed bitmap
is used only if the number of bits in the bitmap does not fit in
the message and there is a gain after compression.
The algorithm is part of libosmocore and so there is dependency
on the libosmocore for compilation.
The algorithm is tested on integration setup by forcing compression.

Change-Id: Id2eec4b5eb6da0ebd24054b541b09b700b9b40ba
9 files changed