scripts: Copy special firmware archives only when requested to sign

Currently pushimage copies firmware_from_source.tar.bz2 to 5 different
locations. They're weird since they contents are identical while their
names suggest that contents are different (e.g. hps_firmware vs.
gsc_firmware).

This patch changes pushimage to copy specialized firmware archives only
when they are requested to sign. The assumption here is that firmware
archives are not useful without signing.

BUG=b:258256803
TEST=./run_tests

Change-Id: Iaee1b2aae731f4d1a5d99161d8670204a7f00232
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/4546962
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Tested-by: Shuhei Takahashi <nya@chromium.org>
Commit-Queue: Shuhei Takahashi <nya@chromium.org>
diff --git a/scripts/pushimage.py b/scripts/pushimage.py
index d07aca6..5bd0288 100644
--- a/scripts/pushimage.py
+++ b/scripts/pushimage.py
@@ -478,6 +478,19 @@
                 "tar.bz2",
                 constants.IMAGE_TYPE_FIRMWARE,
             ),
+        )
+
+        # The following build artifacts are copied and marked for signing, if
+        # they are present *and* if the image type is specified via
+        # |sign_types|.
+        files_to_maybe_copy_and_sign = (
+            # (<src>, <dst>, <suffix>, <signing type>),
+            (
+                constants.BASE_IMAGE_TAR,
+                base_basename,
+                "tar.xz",
+                constants.IMAGE_TYPE_BASE,
+            ),
             (
                 "firmware_from_source.tar.bz2",
                 hps_firmware_basename,
@@ -504,18 +517,6 @@
             ),
         )
 
-        # The following build artifacts are copied and marked for signing, if
-        # they are present *and* if the image type is specified via |sign_types|.
-        files_to_maybe_copy_and_sign = (
-            # (<src>, <dst>, <suffix>, <signing type>),
-            (
-                constants.BASE_IMAGE_TAR,
-                base_basename,
-                "tar.xz",
-                constants.IMAGE_TYPE_BASE,
-            ),
-        )
-
         def _CopyFileToGS(src, dst=None, suffix=None):
             """Returns |dst| file name if the copying was successful."""
             if dst is None: