Previously when user tried to allocate to big bio he recieved NULL. As the
behavior was changed to `BUG()` passing out of range value is no longer legal.
Limiting the requested bio size to BIO_MAX_PAGES (on the older kernels) or to
BIO_MAX_VECS (on the newer ones) eliminates the problem as the macros represent
the max possible value.
Signed-off-by: Michal Mielewczyk <michal.mielewczyk@intel.com>
4753374b1b