Fix AG0092: Add m_tempBuffer buffer initialization to zero and a missing override parameters in deriveTimdMode.

On commit 2c146e1f, valgrind issues were reported. Indeed, in deriveTimdMode function, the secondary TIMD mode is set equal to the primary one. However, the bSecondaryModeCheckWA override was missing, leading to generating prediction based on uninitialized neighboring source sample pixels.

Valgrind tests were run over locally on all D contents. No valgrind issues were detected. Tests using CTC conditions were run to check the conformance of the encodings. No issues were detected.