usb: typec: tipd: declare in_data in as const in exec_cmd functions

The input data passed to execute commands with tps6598x_exec_cmd()
is not supposed to be modified by the function. Moreover, this data is
passed to tps6598x_exec_cmd_tmo() and finally to tps6598x_block_write(),
which expects a const pointer.

The current implementation does not produce any bugs, but it discards
const qualifiers from the pointers passed as arguments. This leads to
compile issues if 'discarded-qualifiers' is active and a const pointer
is passed to the function, which is the case if data from a firmware
structure is passed to execute update commands. Adding the const
modifier to in_data prevents such issues and provides code consistency.
Signed-off-by: Javier Carrasco <javier.carrasco@wolfvision.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20231207-tps6598x_update-v2-3-f3cfcde6d890@wolfvision.netSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/typec/tipd/core.c

@@ -330,7 +330,7 @@ static void tps6598x_disconnect(struct tps6598x *tps, u32 status)
 }
 
 static int tps6598x_exec_cmd_tmo(struct tps6598x *tps, const char *cmd,
-			     size_t in_len, u8 *in_data,
+			     size_t in_len, const u8 *in_data,
 			     size_t out_len, u8 *out_data,
 			     u32 cmd_timeout_ms, u32 res_delay_ms)
 {
@@ -396,7 +396,7 @@ static int tps6598x_exec_cmd_tmo(struct tps6598x *tps, const char *cmd,
 }
 
 static int tps6598x_exec_cmd(struct tps6598x *tps, const char *cmd,
-			     size_t in_len, u8 *in_data,
+			     size_t in_len, const u8 *in_data,
 			     size_t out_len, u8 *out_data)
 {
 	return tps6598x_exec_cmd_tmo(tps, cmd, in_len, in_data,