drm/amdkfd: Align expected_queue_size to PAGE_SIZE

drm/amdkfd: Align expected_queue_size to PAGE_SIZE

The AQL queue size can be 4K, but the minimum buffer object (BO)
allocation size is PAGE_SIZE. On systems with a page size larger
than 4K, the expected queue size does not match the allocated BO
size, causing queue creation to fail.

Align the expected queue size to PAGE_SIZE so that it matches the
allocated BO size and allows queue creation to succeed.

Reviewed-by: Felix Kuehling <felix.kuehling@amd.com>
Signed-off-by: Donet Tom <donettom@linux.ibm.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>