extract-files: Force architecture to be specified

* This also functions as a rudimentary help option
  if the script is run without any arguments,
  or if any of the arguments are not provided

Change-Id: I311df9f52a1dd51da676c3b004a98eefbd79e12e
Signed-off-by: Paul Keith <[email protected]>

extract-files.sh

@@ -51,8 +51,8 @@ if [ -z "$SRC" ]; then
 fi
 
 if [ -z "$TARGET" ]; then
-    echo "Warning, target for extraction not specified, defaulting to arm"
-    TARGET=arm
+    echo "Architecture for extraction not specified! Specify one with --target"
+    exit 1
 fi
 
 # Initialize the helper for common gapps