stagefright: ACodec: query color format support on specific port

This field got uninitialized again due to a wrong merge conflict resolution.

Bug: 27114487
Change-Id: Ie993d3e87e921963e1d76d782b42796069771852
diff --git a/media/libstagefright/ACodec.cpp b/media/libstagefright/ACodec.cpp
index d39fffa..cf88024 100644
--- a/media/libstagefright/ACodec.cpp
+++ b/media/libstagefright/ACodec.cpp
@@ -7095,7 +7095,7 @@
         // prefix "flexible" standard ones with the flexible equivalent
         OMX_VIDEO_PARAM_PORTFORMATTYPE portFormat;
         InitOMXParams(&portFormat);
-        param.nPortIndex = isEncoder ? kPortIndexInput : kPortIndexOutput;
+        portFormat.nPortIndex = isEncoder ? kPortIndexInput : kPortIndexOutput;
         Vector<uint32_t> supportedColors; // shadow copy to check for duplicates
         for (OMX_U32 index = 0; index <= kMaxIndicesToCheck; ++index) {
             portFormat.nIndex = index;