libjpegrecoverymap: bug fix

nameSpaceLength is already +1ed

Test: recoverymap_test
Change-Id: I73a11108bb8f1b2474a518bcbf8460f7e4a672db
diff --git a/libs/jpegrecoverymap/recoverymap.cpp b/libs/jpegrecoverymap/recoverymap.cpp
index 53fa8ce..bc69a83 100644
--- a/libs/jpegrecoverymap/recoverymap.cpp
+++ b/libs/jpegrecoverymap/recoverymap.cpp
@@ -864,7 +864,7 @@
     // 2 bytes: representing the length of the package
     // 29 bytes: length of name space "http://ns.adobe.com/xap/1.0/\0",
     // x bytes: length of xmp packet
-    const int length = 3 + nameSpaceLength + xmp.size();
+    const int length = 2 + nameSpaceLength + xmp.size();
     const uint8_t lengthH = ((length >> 8) & 0xff);
     const uint8_t lengthL = (length & 0xff);
     JPEGR_CHECK(Write(dest, &photos_editing_formats::image_io::JpegMarker::kStart, 1, pos));