This is on a separate branch because during performance testing, this
approach, using a fixed switch statement to determine the mapped entry,
performs much worse than the original lookup table method.
On Ubuntu 16.04, with gcc 5.4 and clang 3.8, the switch case took about
25% more time with clang, but almost 70% more time with gcc compared to
the lookup table.
util_char_map.c is generated at compile time by the Python script
x52_char_map_gen.py from the configuration x52_char_map.cfg. However,
because it was listed in libx52util_la_SOURCES, it was getting added to
the distribution.
In addition, removing it from the distribution caused `make distcheck`
to fail, since the generation script was called relative to the current
directory, instead of relative to `$(srcdir)`. This commit also fixes
that issue.
The conversion makes it simpler to allow cross-compilation, since we
should be using the host Python interpreter to build the generated
character map, rather than relying on the automake infrastructure.