Added parameter to disable itrace

Created by: silabs-hfegran

Simulation performance profiling shows that the itrace module currently exhibits excessive resource usage, added parameter to selectively enable this feature if needed (disabled by default).

(Example: Identical run of corev_rand_instr_test with xcelium had its run time reduced from several hours to 2 minutes when this module was disabled)

Signed-off-by: Henrik Fegran Henrik.Fegran@silabs.com