Makefile.am: Add .arclint and .clang-format to EXTRA_DIST

These files are part of the package, but are not installed by default.

Reviewed-by: Frédéric Dalleau <frederic.dalleau@collabora.com>
Signed-off-by: Justin Kim <justin.kim@collabora.com>
Differential Revision: https://phabricator.apertis.org/D5404

Makefile.am

@@ -10,6 +10,8 @@ pkgconfig_DATA = liblightwood.pc
 
 
 EXTRA_DIST = \
+	.arclint \
+	.clang-format \
 	configure\
 	autogen.sh\
 	$(INTLTOOL_FILES)\