Fix CTS android.hardware.cts.CameraTest#testJpegExif

Bug: 70863791
Test: run CTS
Change-Id: If3a52573a39037d8548ab6428ad97a60f8cadf8d
diff --git a/camera/Exif.cpp b/camera/Exif.cpp
index bd8e93a..f7f85f5 100644
--- a/camera/Exif.cpp
+++ b/camera/Exif.cpp
@@ -450,7 +450,7 @@
         data.insert(data.end(),
                     std::begin(kAsciiPrefix),
                     std::end(kAsciiPrefix));
-        data.insert(data.end(), stringValue, stringValue + strlen(stringValue));
+        data.insert(data.end(), stringValue, stringValue + entry.count);
         createEntry(exifData, EXIF_IFD_GPS, EXIF_TAG_GPS_PROCESSING_METHOD,
                     &data[0], data.size());
     }