Allocating memory with kmalloc and GPF_DMA32 is not allowed, the
allocator will ignore the attribute.

Instead, use dma_alloc_coherent() API as we allocate a small amount of
memory to transfer firmware fragment to the ISH.

On Arcada chromebook, after the patch the warning:
"Unexpected gfp: 0x4 (GFP_DMA32). Fixing up to gfp: 0xcc0 (GFP_KERNEL).  Fix your code!"
is gone. The ISH firmware is loaded properly and we can interact with
the ISH:
> ectool  --name cros_ish version
...
Build info:    arcada_ish_v2.0.3661+3c1a1c1ae0 2022-02-08 05:37:47 @localhost
Tool version:  v2.0.12300-900b03ec7f 2022-02-08 10:01:48 @localhost

Fixes: commit 91b22810 ("HID: intel-ish-hid: ISH firmware loader client driver")
Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jiri Kosina <jkosina@suse.cz>