CRAN gcc-ASAN tests find remaining snprintf()

[ablaette]

From the gcc-ASAN tests (https://www.stats.ox.ac.uk/pub/bdr/memtests/gcc-ASAN/RcppCWB/00install.out)

In file print-modes.c:

print-modes.c: In function ‘ComputePrintStructures’:
print-modes.c:94:5: warning: null destination pointer [-Wformat-truncation=]
94 | snprintf(p, strlen(p), "%s", ai->attribute->any.name);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~