firmware/dmi: Include product_family info to modalias

Some platforms rely on modalias to customize configuration,
the product family helps to identify the hardware.

Add product_family to modalias for better utilization.
This patch mimics commit e26f023 ("firmware/dmi:
Include product_sku info to modalias") that did the same
for product_sku, and commit f97a210 ("firmware: dmi:
Move product_sku info to the end of the modalias") that
fixed regressions caused by the added field not being in
the end of the list.

Signed-off-by: Antoine Lassagne <antoine.lassagne@canonical.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>

Author: antlassagne

drivers/firmware/dmi-id.c

@@ -96,6 +96,7 @@ static ssize_t get_modalias(char *buffer, size_t buffer_size)
 		{ "ct",  DMI_CHASSIS_TYPE },
 		{ "cvr", DMI_CHASSIS_VERSION },
 		{ "sku", DMI_PRODUCT_SKU },
+		{ "pfa", DMI_PRODUCT_FAMILY },
 		{ NULL,  DMI_NONE }
 	};