Add initial support for AT_RSEQ_*

In newer operating systems AT_RSEQ_* parameters are automatically
added to binaries. This does not mean that the application
uses rseq, but it is a possibility. Currently we do not support
rseq as it is a complex issue, so for now we allow AT_RSEQ_* to
be passed, however a warning is printed, as there are no
guarantees rseq will not be used by the binary. In most of the
cases however resq is not used and majority of binaries should run
without any issues.

elf/elf_loader.c

@@ -377,6 +377,12 @@ void elf_run(uintptr_t entry_address, char *filename, int argc, char **argv, cha
         d_aux->a_un.a_val = s_aux->a_un.a_val;
         break;
 
+      case AT_RSEQ_FEATURE_SIZE:
+      case AT_RSEQ_ALIGN:
+        fprintf(stderr, "MAMBO: AT_RSEQ_* found! Repeatable sequences (rseq) are not currently supported!\n");
+        d_aux->a_un.a_val = s_aux->a_un.a_val;
+        break;
+
       case AT_RANDOM: {
         stack_strings -= 15;
         memcpy(stack_strings, (void *)s_aux->a_un.a_val, 16);