Input: ims-pcu - annotate struct ims_pcu_flash_fmt with __counted_by

Use the __counted_by compiler attribute for the data[] flexible array
member to improve the results of array bound sanitizers.
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Reviewed-by: Kees Cook <kees@kernel.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20240619-ims-pcu-counted_by-v1-1-3ee0ead2e57d@gmail.comSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/misc/ims-pcu.c

@@ -761,7 +761,7 @@ static int ims_pcu_switch_to_bootloader(struct ims_pcu *pcu)
 struct ims_pcu_flash_fmt {
 	__le32 addr;
 	u8 len;
-	u8 data[];
+	u8 data[] __counted_by(len);
 };
 
 static unsigned int ims_pcu_count_fw_records(const struct firmware *fw)