In order to continue to support Automake builds, we need to update the
source to comply with C90 standards, as well as ignoring the warnings in
the test binary.
This change adds a test suite for libx52util, testing all the positive
cases where a character is added to the lookup table. For now, this test
suite only verifies single character mappings, not double character
mappings. A future commit will add test cases for characters not in the
map.
On some systems (notably FreeBSD), the make implementation makes a
distinction between $(builddir)/<path> and <path>, even when builddir is
`.`. This commit removes $(builddir) from all references to generated
files, so that these implementations don't fail. Keeping $(builddir)
causes older versions automake (1.15 and older) to generate a broken
Makefile.
nirenjan