Reading security memory may take longer if system time unit runs in non-default mode

The function DELAY_ONE_CLOCK from Drv_Sec.c uses the System-Time registers to delay execution. Unfortunately it assumes a clock add value of 10. This is wrong for some Realtime Ethernet systems where the clock add value is around 1 because of ethernet frame timestamping. Time reading the secmem increases by factor of 10 on second system start. (Debugger, First start: clock add value will be set to 1 after secmem has been read. Stop,ResetRegisters Second start: now clock add value is at one and reading secmem takes long time.)