CI: Fix unmigrated symbol test

When calling comm to compare the CONFIG symbols a defconfig uses with
the symbols that have been migrated, we need to suppress all output as
the summary line will have everything we need.  Failure to do this leads
to the test blowing up, but in non-fatal ways.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/.azure-pipelines.yml b/.azure-pipelines.yml
index cf49161..0f1a1bd 100644
--- a/.azure-pipelines.yml
+++ b/.azure-pipelines.yml
@@ -71,7 +71,7 @@
              grep '#define[[:blank:]]CONFIG_' $CFG | \
                 sed -n 's/#define.\(CONFIG_[A-Za-z0-9_]*\).*/\1/p' | \
                 sort -u > ${KUSEDLST} || true
-             NUM=`comm -12 --total --output-delimiter=, ${KSYMLST} ${KUSEDLST} | \
+             NUM=`comm -123 --total --output-delimiter=, ${KSYMLST} ${KUSEDLST} | \
                 cut -d , -f 3`
              if [[ $NUM -ne 0 ]]; then
                 echo "Unmigrated symbols found in $CFG"