util/testing: Ensure coreboot-gerrit fails if libpayload build fails

The JUnit output from the libpayload builds was getting deleted by the
coreinfo build.  Move the libpayload to later in the coreboot-gerrit
job.

Also add messages to stdout indicating the various libpayload configs
that are built and a message indicating when all libpayload builds are
complete.

BUG=b:137380189
TEST=Upload test commit that includes a libpayload compile error and
verify buildbot fails.

Change-Id: I43b55f402216582dcf81be34171437be345572ab
Signed-off-by: Keith Short <keithshort@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34183
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

payloads/libpayload/Makefile.inc

@@ -130,6 +130,7 @@ junit.xml:
 	echo '<?xml version="1.0" encoding="utf-8"?><testsuite>' > $@.tmp
 	for i in $(filter-out %.old,$(wildcard configs/*)); do \
 		$(MAKE) clean; \
+		echo "Building libpayload for $$i"; \
 		cp "$$i" junit_config; \
 		$(MAKE) olddefconfig DOTCONFIG=junit_config V=$(V) Q=$(Q) 2>/dev/null >/dev/null; \
 		echo "<testcase classname='libpayload' name='$$i'>" >> $@.tmp; \
@@ -146,6 +147,7 @@ junit.xml:
 		echo "</testcase>" >> $@.tmp; \
 	done
 	echo "</testsuite>" >> $@.tmp
+	echo "libpayload build complete, test results in $@"
 	mv $@.tmp $@
 
 test-configs: