util/testing: Allow what-jenkins-does to skip lint testing

The linters touch every file under src and probably util.  This makes
it difficult to see what files have been accessed by the builder.

The JENKINS_SKIP_LINT_TESTS variable will only be set on the jenkins
build that looks for unused files.

Signed-off-by: Martin Roth <martin@coreboot.org>
Change-Id: I12fa31641c2a72c5e07be1c4958467f7165f21bb
Reviewed-on: https://review.coreboot.org/c/coreboot/+/46807
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
diff --git a/util/testing/Makefile.inc b/util/testing/Makefile.inc
index 8872884..d094196 100644
--- a/util/testing/Makefile.inc
+++ b/util/testing/Makefile.inc
@@ -79,8 +79,10 @@
 
 what-jenkins-does:
 	rm -rf $(COREBOOT_BUILD_DIR)/chromeos $(COREBOOT_BUILD_DIR)/default
+ifneq ($(JENKINS_SKIP_LINT_TESTS),y)
 	util/lint/lint lint-stable --junit
 	util/lint/lint lint-extended --junit
+endif
 	util/abuild/abuild -o $(COREBOOT_BUILD_DIR)/chromeos $(ABUILD_OPTIONS) -x -X $(top)/abuild-chromeos.xml
 	util/abuild/abuild -o $(COREBOOT_BUILD_DIR)/default $(ABUILD_OPTIONS)
 	$(foreach tool, $(TOOLLIST), $(MAKE) CPUS=$(CPUS) V=$(V) Q=$(Q) BLD_DIR="util/$(tool)" BLD="$(tool)" MFLAGS= MAKEFLAGS= MAKETARGET= junit.xml; )