Check os_snprintf() result more consistently - success case

Check os_snprintf() result more consistently - success case

This converts os_snprintf() result validation cases to use
os_snprintf_error() in cases where success condition was used to execute
a step. These changes were done automatically with spatch using the
following semantic patch:

@@
expression E1,E2,E3;
statement S1;
@@

  E1 = os_snprintf(E2, E3, ...);
- if (\( E1 >= 0 \| E1 > 0 \) && \( (size_t) E1 < E3 \| E1 < (int) E3 \| E1 < E3 \))
+ if (!os_snprintf_error(E3, E1))
  S1

Signed-off-by: Jouni Malinen <j@w1.fi>