Fixing memory leak while feeing sparsity pattern (#9166)

Author: AnHeuermann

OMCompiler/SimulationRuntime/c/simulation/solver/nonlinearSystem.c

@@ -451,6 +451,7 @@ void initializeNonlinearSystemData(DATA *data, threadData_t *threadData, NONLINE
       /* DEBUG */
       //printSparseStructure(nonlinsys->sparsePattern, nonlinsys->size, nonlinsys->size, LOG_NLS, "NLS sparse pattern");
       freeSparsePattern(nonlinsys->sparsePattern);
+      free(nonlinsys->sparsePattern);
       nonlinsys->sparsePattern = NULL;
       nonlinsys->isPatternAvailable = FALSE;
       omc_flag[FLAG_NO_SCALING] = TRUE;