platform/x86: think-lmi: Clean up display of current_value on Thinkstation

On ThinkStations on retrieving the attribute value the BIOS appends the
possible values to the string.
Clean up the display in the current_value_show function so the options
part is not displayed.

Fixes: a40cd7e ("platform/x86: think-lmi: Add WMI interface support on Lenovo platforms")
Reported by Mario Limoncello <Mario.Limonciello@amd.com>
Link: fwupd/fwupd#5077 (comment)
Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://lore.kernel.org/r/20230403013120.2105-2-mpearson-lenovo@squebb.ca
Tested-by: Mario Limonciello <mario.limonciello@amd.com>
Tested-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Author: mrhpearson

drivers/platform/x86/think-lmi.c

@@ -920,7 +920,7 @@ static ssize_t display_name_show(struct kobject *kobj, struct kobj_attribute *at
 static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 {
 	struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj);
-	char *item, *value;
+	char *item, *value, *p;
 	int ret;
 
 	ret = tlmi_setting(setting->index, &item, LENOVO_BIOS_SETTING_GUID);
@@ -931,9 +931,12 @@ static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *a
 	value = strpbrk(item, ",");
 	if (!value || value == item || !strlen(value + 1))
 		ret = -EINVAL;
-	else
+	else {
+		/* On Workstations remove the Options part after the value */
+		p = strchrnul(value, ';');
+		*p = '\0';
 		ret = sysfs_emit(buf, "%s\n", value + 1);
-
+	}
 	kfree(item);
 
 	return ret;