i2c: st: fix missing struct parameter description

BugLink: https://bugs.launchpad.net/bugs/1875905

[ Upstream commit f491c668 ]

Fix a missing struct parameter description to allow
warning free W=1 compilation.
Signed-off-by: Alain Volmat <avolmat@me.com>
Reviewed-by: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Ian May <ian.may@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

drivers/i2c/busses/i2c-st.c

@@ -399,6 +399,7 @@ static void st_i2c_wr_fill_tx_fifo(struct st_i2c_dev *i2c_dev)
 /**
  * st_i2c_rd_fill_tx_fifo() - Fill the Tx FIFO in read mode
  * @i2c_dev: Controller's private data
+ * @max: Maximum amount of data to fill into the Tx FIFO
  *
  * This functions fills the Tx FIFO with fixed pattern when
  * in read mode to trigger clock.