Initialize OpenEXROutput::m_levelmode() in init(). (AcademySoftwareFoundation#3764)

Avoids conditional jump on uninitialised values in close().

Co-authored-by: Joachim Reichel <[email protected]>

Author: 2 people

src/openexr.imageio/exroutput.cpp

@@ -190,6 +190,7 @@ class OpenEXROutput final : public ImageOutput {
         m_tiled_output_part.reset();
         m_deep_scanline_output_part.reset();
         m_deep_tiled_output_part.reset();
+        m_levelmode = Imf::ONE_LEVEL;
         m_subimage = -1;
         m_miplevel = -1;
         m_subimagespecs.clear();