Input: sentelic - fix error return when fsp_reg_write fails

BugLink: https://bugs.launchpad.net/bugs/1892822

[ Upstream commit ea38f06e ]

Currently when the call to fsp_reg_write fails -EIO is not being returned
because the count is being returned instead of the return value in retval.
Fix this by returning the value in retval instead of count.

Addresses-Coverity: ("Unused value")
Fixes: fc69f4a6 ("Input: add new driver for Sentelic Finger Sensing Pad")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20200603141218.131663-1-colin.king@canonical.comSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Ian May <ian.may@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

drivers/input/mouse/sentelic.c

@@ -454,7 +454,7 @@ static ssize_t fsp_attr_set_setreg(struct psmouse *psmouse, void *data,
 
 	fsp_reg_write_enable(psmouse, false);
 
-	return count;
+	return retval;
 }
 
 PSMOUSE_DEFINE_WO_ATTR(setreg, S_IWUSR, NULL, fsp_attr_set_setreg);