lib: fortify_kunit: build without structleak plugin
Building allmodconfig with aarch64-linux-gnu-gcc (Debian 11.3.0-6),
fortify_kunit with strucleak plugin enabled makes the stack frame size
to grow too large:
lib/fortify_kunit.c:140:1: error: the frame size of 2368 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]
Turn off the structleak plugin checks for fortify_kunit.