media: venus: hfi_cmds.h: Replace one-element array with flexible-array member

There is a regular need in the kernel to provide a way to declare having
a dynamically sized set of trailing elements in a structure. Kernel code
should always use “flexible array members”[1] for these cases. The older
style of one-element or zero-length arrays should no longer be used[2].

Use flexible-array member in struct hfi_sys_set_property_pkt instead of
one-element array.

Also, this helps with the ongoing efforts to enable -Warray-bounds and
fix the following warnings:

drivers/media/platform/qcom/venus/hfi_cmds.c: In function ‘pkt_sys_coverage_config’:
drivers/media/platform/qcom/venus/hfi_cmds.c:57:11: warning: array subscript 1 is above array bounds of ‘u32[1]’ {aka ‘unsigned int[1]’} [-Warray-bounds]
   57 |  pkt->data[1] = mode;
      |  ~~~~~~~~~^~~

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9/process/deprecated.html#zero-length-and-one-element-arrays

Link: https://github.com/KSPP/linux/issues/79
Link: https://github.com/KSPP/linux/issues/109Build-tested-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/602416da.iZqae7Dbk7nyl6OY%25lkp@intel.com/Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/platform/qcom/venus/hfi_cmds.h

@@ -68,7 +68,7 @@ struct hfi_sys_release_resource_pkt {
 struct hfi_sys_set_property_pkt {
 	struct hfi_pkt_hdr hdr;
 	u32 num_properties;
-	u32 data[1];
+	u32 data[];
 };
 
 struct hfi_sys_get_property_pkt {