buildman: Add --allow-missing flag to allow missing blobs

Add a new flag to buildman so that we will in turn pass
BINMAN_ALLOW_MISSING=1 to 'make'. Make use of this flag in CI.

Allow the settings file to control this.

Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Cc: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 6f4c34f..3deaeca 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -81,7 +81,7 @@
   stage: world build
   script:
     - ret=0;
-      ./tools/buildman/buildman -o /tmp -P -E -W arm -x aarch64 || ret=$?;
+      ./tools/buildman/buildman -o /tmp -PEWM arm -x aarch64 || ret=$?;
       if [[ $ret -ne 0 ]]; then
         ./tools/buildman/buildman -o /tmp -seP;
         exit $ret;
@@ -93,7 +93,7 @@
     - virtualenv -p /usr/bin/python3 /tmp/venv
     - . /tmp/venv/bin/activate
     - ret=0;
-      ./tools/buildman/buildman -o /tmp -P -E -W aarch64 || ret=$?;
+      ./tools/buildman/buildman -o /tmp -PEWM aarch64 || ret=$?;
       if [[ $ret -ne 0 ]]; then
         ./tools/buildman/buildman -o /tmp -seP;
         exit $ret;
@@ -113,7 +113,7 @@
   stage: world build
   script:
     - ret=0;
-      ./tools/buildman/buildman -o /tmp -P -E -W -x arm,powerpc || ret=$?;
+      ./tools/buildman/buildman -o /tmp -PEWM -x arm,powerpc || ret=$?;
       if [[ $ret -ne 0 ]]; then
         ./tools/buildman/buildman -o /tmp -seP;
         exit $ret;