videoio: drop unnecessary offset for accessing video output buffer

Fix: #21021

NDK API AMediaCodec_getOutputBuffer() returns MediaCodecBuffer::data()
which is actually ABuffer::data(). The returned buffer address is already
adjusted by offset.

More info:
    ABuffer::base() returns base address without offset
    ABuffer::data() returns base + offset

Change-Id: I2936339ce4fa9acf657a5a7d92adc1275d7b28a1

modules/videoio/src/cap_android_mediandk.cpp

@@ -92,7 +92,7 @@ public:
                     AMediaFormat_getInt32(mediaFormat.get(), AMEDIAFORMAT_KEY_HEIGHT, &frameHeight);
                     AMediaFormat_getInt32(mediaFormat.get(), AMEDIAFORMAT_KEY_COLOR_FORMAT, &colorFormat);
                     uint8_t* codecBuffer = AMediaCodec_getOutputBuffer(mediaCodec.get(), bufferIndex, &bufferSize);
-                    buffer = std::vector<uint8_t>(codecBuffer + info.offset, codecBuffer + bufferSize);
+                    buffer = std::vector<uint8_t>(codecBuffer, codecBuffer + bufferSize);
                     LOGV("colorFormat: %d", colorFormat);
                     LOGV("buffer size: %zu", bufferSize);
                     LOGV("width (frame): %d", frameWidth);