This patch renames filter-lexer.l to filter-lexer.lpp and
filter-parser.y to filter-parser.ypp. That makes automake pass the
right options to flex/bison to generate C++ code.
In filter-lexer.lpp, Instead of having declarations with the `unused`
attribute for yyunput and yyinput, use the noinput and nounput options.
The rest of the changes are standard C to C++ conversion stuff.
Change-Id: Ie4bf1981b970145f97e8db1d88edaa2d9b95aef4
Signed-off-by: Simon Marchi <simon.marchi@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>