extract_firmware: Unsparse images before copying

Some OEMs like motorola ship sparse images which can't be flashed as-is

Change-Id: I6f5a7e058e02167c242b0a5053fa4f6cc3a351ea
diff --git a/extract_utils.sh b/extract_utils.sh
index 0d3d154..cac51b5 100644
--- a/extract_utils.sh
+++ b/extract_utils.sh
@@ -1969,6 +1969,10 @@
             elif [ -f "$SRC/$DST_FILE" ]; then
                 COPY_FILE="$SRC/$DST_FILE"
             fi
+            if [[ $(file -b "$COPY_FILE") == Android* ]]; then
+                "$SIMG2IMG" "$COPY_FILE" "$SRC"/"$(basename "$COPY_FILE").raw"
+                COPY_FILE="$SRC"/"$(basename "$COPY_FILE").raw"
+            fi
         fi
 
         if [ -f "$COPY_FILE" ]; then