remove dashes and and sort tests

remove dashes on 'make help_tests' output aligns a bit more to main 'make
help' output. Also, sort tests sets so users find quicker the name of the test.

Signed-off-by: Leonardo Sandoval <leonardo.sandoval@linaro.org>
Change-Id: If09992ddff95865233b1a311f9a52600d3756556
diff --git a/tftf/tests/tests.mk b/tftf/tests/tests.mk
index f5414e2..ebe090c 100644
--- a/tftf/tests/tests.mk
+++ b/tftf/tests/tests.mk
@@ -8,11 +8,12 @@
 
 tests_files	:= $(wildcard tftf/tests/*.xml)
 tests_sets	:= $(patsubst tftf/tests/tests-%.xml,%,${tests_files})
+tests_sets	:= $(sort ${tests_sets})
 
 PHONY: help_tests
 help_tests:
-	@echo "Available sets of tests:"
-	@$(foreach t, ${tests_sets}, printf " - %s\n" ${t};)
+	@echo "Supported Tests:"
+	@$(foreach t, ${tests_sets}, printf "   %s\n" ${t};)
 
 TESTS_FILE	:= tftf/tests/tests-${TESTS}.xml
 TESTS_MAKEFILE	:= tftf/tests/tests-${TESTS}.mk