thinkpad-acpi fails to load with newer Thinkpad X201s BIOS

The new BIOS has a slightly different EC version string.

From a1541710300b083a1a9acff2890d721d15ede62b Mon Sep 17 00:00:00 2001
From: Keith Packard <keithp@keithp.com>
Date: Sun, 13 Mar 2011 23:46:22 -0700
Subject: [PATCH] thinkpad-acpi: Some BIOS versions don't end in WW, remove check

My X201s BIOS version string is 6QET46V1 (1.16 ). The
EC version string is 6QHT28WW-1.09. The driver was requiring that both
of these have 'WW' in positions 6 and 7. I don't know what the
significance of having 'V1' there instead is, but removing the test
makes the driver load on my machine.
Signed-off-by: NKeith Packard <keithp@keithp.com>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>

drivers/platform/x86/thinkpad_acpi.c

@@ -8618,8 +8618,7 @@ static bool __pure __init tpacpi_is_valid_fw_id(const char* const s,
 		tpacpi_is_fw_digit(s[1]) &&
 		s[2] == t && s[3] == 'T' &&
 		tpacpi_is_fw_digit(s[4]) &&
-		tpacpi_is_fw_digit(s[5]) &&
-		s[6] == 'W' && s[7] == 'W';
+		tpacpi_is_fw_digit(s[5]);
 }
 
 /* returns 0 - probe ok, or < 0 - probe error.