accel/qaic: Use kvcalloc() for slice requests allocation

accel/qaic: Use kvcalloc() for slice requests allocation

When a BO is created, qaic will use the page allocator to request the
memory chunks that the BO will be composed of in-memory. The number of
chunks increases when memory is segmented. For example, a 16MB BO can
be composed of four 4MB chunks or 4096 4KB chunks.

A BO is then sliced into a single or multiple slices to be transferred
to the device on the DBC's xfer queue. For that to happen, the slice
needs to encode its memory chunks into DBC requests and keep track of
them in an array, which is allocated using kcalloc(). Knowing that the
BO might be very fragmented, this array can grow so large that the
allocation may fail to find contiguous memory for it.

Replace kcalloc() with kvcalloc() to allocate the DBC requests array
for a slice.

Signed-off-by: Youssef Samir <quic_yabdulra@quicinc.com>
Signed-off-by: Youssef Samir <youssef.abdulrahman@oss.qualcomm.com>
Reviewed-by: Jeff Hugo <jeff.hugo@oss.qualcomm.com>
Reviewed-by: Carl Vanderlip <carl.vanderlip@oss.qualcomm.com>
Signed-off-by: Jeff Hugo <jeff.hugo@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20251007121845.337382-1-youssef.abdulrahman@oss.qualcomm.com