build: Fix “make distcheck” errors

Ship the doc/lcov-{epi,pro}log files created in commit
0581dda824f26e9eec996ebf4de5f6474336bec2 in the distribution tarball,
as well as the dpkg-divert test that moved in commit
577ab5dd513beb641f1d635d8ead681065254233.

Makefile.am

@@ -28,6 +28,8 @@ EXTRA_DIST = \
 	doc/README.api \
 	doc/README.feature-removal-schedule \
 	doc/coding-style.txt \
+	doc/lcov-epilog \
+	doc/lcov-prolog \
 	doc/triggers.txt \
 	debian/archtable \
 	debian/changelog \

src/Makefile.am

@@ -11,6 +11,9 @@ AM_CPPFLAGS = \
 	-I$(top_srcdir)/lib
 
 
+EXTRA_DIST = \
+	$(test_cases)
+
 bin_PROGRAMS = \
 	dpkg \
 	dpkg-divert \