[libata] ata_piix: cleanup dmi strings checking

Commit
	ATA: piix, fix pointer deref on suspend
fixed a possible oops in an ugly manner. Use newly introduced dmi_match()
to make the code pretty again.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Alexandru Romanescu <a_romanescu@yahoo.co.uk>
Cc: Tejun Heo <tj@kernel.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/ata/ata_piix.c

@@ -1072,20 +1072,13 @@ static int piix_broken_suspend(void)
 	 * matching is necessary because dmi_system_id.matches is
 	 * limited to four entries.
 	 */
-	if (dmi_get_system_info(DMI_SYS_VENDOR) &&
-	    dmi_get_system_info(DMI_PRODUCT_NAME) &&
-	    dmi_get_system_info(DMI_PRODUCT_VERSION) &&
-	    dmi_get_system_info(DMI_PRODUCT_SERIAL) &&
-	    dmi_get_system_info(DMI_BOARD_VENDOR) &&
-	    dmi_get_system_info(DMI_BOARD_NAME) &&
-	    dmi_get_system_info(DMI_BOARD_VERSION) &&
-	    !strcmp(dmi_get_system_info(DMI_SYS_VENDOR), "TOSHIBA") &&
-	    !strcmp(dmi_get_system_info(DMI_PRODUCT_NAME), "000000") &&
-	    !strcmp(dmi_get_system_info(DMI_PRODUCT_VERSION), "000000") &&
-	    !strcmp(dmi_get_system_info(DMI_PRODUCT_SERIAL), "000000") &&
-	    !strcmp(dmi_get_system_info(DMI_BOARD_VENDOR), "TOSHIBA") &&
-	    !strcmp(dmi_get_system_info(DMI_BOARD_NAME), "Portable PC") &&
-	    !strcmp(dmi_get_system_info(DMI_BOARD_VERSION), "Version A0"))
+	if (dmi_match(DMI_SYS_VENDOR, "TOSHIBA") &&
+	    dmi_match(DMI_PRODUCT_NAME, "000000") &&
+	    dmi_match(DMI_PRODUCT_VERSION, "000000") &&
+	    dmi_match(DMI_PRODUCT_SERIAL, "000000") &&
+	    dmi_match(DMI_BOARD_VENDOR, "TOSHIBA") &&
+	    dmi_match(DMI_BOARD_NAME, "Portable PC") &&
+	    dmi_match(DMI_BOARD_VERSION, "Version A0"))
 		return 1;
 
 	return 0;