make possible to turn off at compile time online debugging, logging
and external sync functionality

Defines TARGET_DEBUG_DISABLE, TARGET_LOGGING_DISABLE, TARGET_EXT_SYNC_DISABLE
allow to use generated PLC code in low-cost microcontrollers,
integrate into external programs and so on.

main.c:
extern void __run(void);
int main(void)
{
for(;;) {
__run();
// sleep common_ticktime__ ns
// add common_ticktime__ ns to __CURRENT_TIME
}
return 0;
}

Compile for example for arm bare-metal:
../build$ arm-none-eabi-gcc \
-DTARGET_DEBUG_DISABLE -DTARGET_LOGGER_DISABLE
-DTARGET_EXT_SYNC_DISABLE \
-flto -ffunction-sections -fdata-sections -I../../../../matiec/lib/C \
*.c \
-nodefaultlibs --specs=nano.specs -Wl,--static -Wl,--gc-section -Wl,--start-group -lc -lm -lnosys -lgcc -Wl,--end-group

BEREMIZ_OBJS = $(BEREMIZSRC:.c=.o)

all: warn some_binary
	@echo "*** all done ***"

warn:
	@echo "*** Sample Makefile, does nothing ***"

some_binary: $(BEREMIZ_OBJS)
	@echo "* Would link $^ -> $@"

%.o: %.c
	@echo "* Would compile $< -> $@"