I am writing here because I have confronted the same problem and I am wondering if you were able to find a solution.

I am trying to compile wolfSSL from scratch in Vitis 2023.1 for a Standalone OS running on psu_cortexa53_0. I initially faced the "define versal" issue, but I managed to resolve it. However, now I am stuck with this error:

C:\wolfssl/wolfssl/wolfcrypt/port/xilinx/xil-versal-glue.h:29:10: fatal error: xsecure_mailbox.h: No such file or directory
   29 | #include <xsecure_mailbox.h>
      |          ^~~~~~~~~~~~~~~~~~~
compilation terminated.
make: *** [src/wolfcrypt/test/subdir.mk:20: src/wolfcrypt/test/test.o] Error 1
I have already enabled the xsecure library in the BSP settings, but I still get the same error.. I also tried regenerating the BSP, manually adding include paths.
If you found a solution to this issue, I would really appreciate it if you could share how you fixed it.