trace: Add a test

Add a test which runs sandbox, collects a trace and makes sure it can
be processed by trace-cmd. This should ensure that this feature continues
to work as U-Boot and trace-cmd evolve.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/.azure-pipelines.yml b/.azure-pipelines.yml
index 5673bb7..74cc8dc 100644
--- a/.azure-pipelines.yml
+++ b/.azure-pipelines.yml
@@ -240,6 +240,11 @@
           TEST_PY_TEST_SPEC: "test_ofplatdata or test_handoff or test_spl"
         sandbox_flattree:
           TEST_PY_BD: "sandbox_flattree"
+        sandbox_trace:
+          TEST_PY_BD: "sandbox"
+          BUILD_ENV: "FTRACE=1 NO_LTO=1"
+          TEST_PY_TEST_SPEC: "trace"
+          OVERRIDE: "-a CONFIG_TRACE=y -a CONFIG_TRACE_EARLY=y -a CONFIG_TRACE_EARLY_SIZE=0x01000000"
         coreboot:
           TEST_PY_BD: "coreboot"
           TEST_PY_ID: "--id qemu"
@@ -362,6 +367,9 @@
           # the below corresponds to .gitlab-ci.yml "script"
           cd ${WORK_DIR}
           export UBOOT_TRAVIS_BUILD_DIR=/tmp/${TEST_PY_BD};
+          if [ -n "${BUILD_ENV}" ]; then
+              export ${BUILD_ENV};
+          fi
           tools/buildman/buildman -o ${UBOOT_TRAVIS_BUILD_DIR} -w -E -W -e --board ${TEST_PY_BD} ${OVERRIDE}
           cp ~/grub_x86.efi ${UBOOT_TRAVIS_BUILD_DIR}/
           cp ~/grub_x64.efi ${UBOOT_TRAVIS_BUILD_DIR}/