The AR#60900 suggests that XSmc_NorInit() should be added to InitNor() in the bootloader.
The XSmc_NorInit() was removed from smc.h, by Xilinx, so I guess XSmc_NorInit() should no longer be a problem.
Still, my code crashes on access to NOR memory in the bootloader.
I used SDK 2017.3
I ended up using the XilFlash library although it is to big to fit in debug mode.