sparc64: Suppress kmalloc (DAX driver) warning due to allocation failure

sparc64: Suppress kmalloc (DAX driver) warning due to allocation failure

dax_alloc is used by libdax to allocate 4MB chunks of physically
contiguous memory using kmalloc. It is normal for dax_alloc to fail
when kmalloc runs out of memory and this should not be treated as a warning.
This failure should be caught in libdax and attempted to allocate memory
from another source (Eg: mmap hugepage).

Orabug: 26224254

Signed-off-by: Sanath Kumar <sanath.s.kumar@oracle.com>
Reviewed-by: Rob Gardner <rob.gardner@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Signed-off-by: Allen Pais <allen.pais@oracle.com>