Makefile: Add rules to run vm tests

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Fam Zheng <famz@redhat.com>
diff --git a/Makefile b/Makefile
index eb831b9..d1501a0 100644
--- a/Makefile
+++ b/Makefile
@@ -811,6 +811,7 @@
 -include $(wildcard *.d tests/*.d)
 
 include $(SRC_PATH)/tests/docker/Makefile.include
+include $(SRC_PATH)/tests/vm/Makefile.include
 
 .PHONY: help
 help:
@@ -834,6 +835,7 @@
 	@echo  'Test targets:'
 	@echo  '  check           - Run all tests (check-help for details)'
 	@echo  '  docker          - Help about targets running tests inside Docker containers'
+	@echo  '  vm-test         - Help about targets running tests inside VM'
 	@echo  ''
 	@echo  'Documentation targets:'
 	@echo  '  html info pdf txt'