patch 8.1.0592: the libvterm tests are not run as part of Vim tests

Problem:    The libvterm tests are not run as part of Vim tests.
Solution:   Add testing libvterm.

src/Makefile

@@ -2107,7 +2107,7 @@ types.vim: $(TAGS_SRC) $(TAGS_INCL)
 # TESTING
 #
 # Execute the test scripts and the unittests.
-test check: scripttests unittests
+test check: scripttests unittests test_libvterm
 
 # Execute the test scripts.  Run these after compiling Vim, before installing.
 # This doesn't depend on $(VIMTARGET), because that won't work when configure
@@ -2159,6 +2159,10 @@ run_memfile_test: $(MEMFILE_TEST_TARGET)
 run_message_test: $(MESSAGE_TEST_TARGET)
 	$(VALGRIND) ./$(MESSAGE_TEST_TARGET) || exit 1; echo $* passed;
 
+# Run the libvterm tests.
+test_libvterm:
+	cd libvterm; $(MAKE) -f Makefile test CC="$(CC)"
+
 # Run individual OLD style test.
 # These do not depend on the executable, compile it when needed.
 test1 \

src/libvterm/Makefile

@@ -8,8 +8,7 @@ ifneq ($(VERBOSE),1)
   LIBTOOL +=--quiet
 endif
 
-# override CFLAGS +=-Wall -Iinclude -std=c99 -DINLINE="static inline" -DUSE_INLINE
-override CFLAGS +=-Wall -Iinclude -std=c90 -Wpedantic -DINLINE=""
+override CFLAGS +=-Wall -Iinclude -std=c99 -Wpedantic -DINLINE=""
 
 ifeq ($(shell uname),SunOS)
   override CFLAGS +=-D__EXTENSIONS__ -D_XPG6 -D__XOPEN_OR_POSIX

src/version.c

@@ -799,6 +799,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    592,
 /**/
     591,
 /**/