Add a 'make tcheck' option to test tools

Running all the unit tests takes a while and is not useful when you are
just modifying the tools. Add an option to run only the tools tests.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/Makefile b/Makefile
index b8a4b50..b56250a 100644
--- a/Makefile
+++ b/Makefile
@@ -512,7 +512,7 @@
 
 no-dot-config-targets := clean clobber mrproper distclean \
 			 help %docs check% coccicheck \
-			 ubootversion backup tests check qcheck
+			 ubootversion backup tests check qcheck tcheck
 
 config-targets := 0
 mixed-targets  := 0
@@ -2098,6 +2098,7 @@
 	@echo  ''
 	@echo  '  check           - Run all automated tests that use sandbox'
 	@echo  '  qcheck          - Run quick automated tests that use sandbox'
+	@echo  '  tcheck          - Run quick automated tests on tools'
 	@echo  ''
 	@echo  'Other generic targets:'
 	@echo  '  all		  - Build all necessary images depending on configuration'
@@ -2143,6 +2144,9 @@
 qcheck:
 	$(srctree)/test/run quick
 
+tcheck:
+	$(srctree)/test/run tools
+
 # Documentation targets
 # ---------------------------------------------------------------------------
 DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \