binman: Use binary mode when compressing data

The lz4 utility inserts binary data in its output which cannot always be
converted to unicode (nor should it be). Fix this by using the new binary
mode for program output.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/binman/etype/blob.py b/tools/binman/etype/blob.py
index ae80bbe..f56a1f8 100644
--- a/tools/binman/etype/blob.py
+++ b/tools/binman/etype/blob.py
@@ -60,7 +60,7 @@
             except AttributeError:
                 data = lz4.compress(data)
             '''
-            data = tools.Run('lz4', '-c', self._pathname)
+            data = tools.Run('lz4', '-c', self._pathname, binary=True)
         self.SetContents(data)
         return True
 
diff --git a/tools/binman/ftest.py b/tools/binman/ftest.py
index 1111852..4d96933 100644
--- a/tools/binman/ftest.py
+++ b/tools/binman/ftest.py
@@ -1557,7 +1557,7 @@
         out = os.path.join(self._indir, 'lz4.tmp')
         with open(out, 'wb') as fd:
             fd.write(data)
-        return tools.Run('lz4', '-dc', out)
+        return tools.Run('lz4', '-dc', out, binary=True)
         '''
         try:
             orig = lz4.frame.decompress(data)