malloc: check size hint when reserving the biggest element
malloc: check size hint when reserving the biggest element

RTE_MEMZONE_SIZE_HINT_ONLY wasn't checked in any way,
causing size hints to be parsed as hard requirements.
This resulted in some allocations being failed prematurely.

Fixes: 68b6092bd3c7 ("malloc: allow reserving biggest element")
Cc: stable@dpdk.org

Signed-off-by: Darek Stojaczyk <9bb9fe07973aa3b8e429d8841c4c0e621c448a50@intel.com>
Reviewed-by: Anatoly Burakov <814e00d8f6e4e81b7ccc7e3e5a0bfec0078f0203@intel.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk