hwmon: (it87) Check the it87_lock() return value

hwmon: (it87) Check the it87_lock() return value

Return early in it87_resume() if it87_lock() fails instead of ignoring the
return value of that function. This patch suppresses a Clang thread-safety
warning.

Cc: Frank Crawford <frank@crawford.emu.id.au>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Jean Delvare <jdelvare@suse.com>
Cc: linux-hwmon@vger.kernel.org
Fixes: 376e1a937b30 ("hwmon: (it87) Add calls to smbus_enable/smbus_disable as required")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20260223220102.2158611-15-bart.vanassche@linux.dev
[groeck: Declare 'ret' at the beginning of it87_resume()]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>