thinkpad-acpi: Fix procfs hotkey reset command

echo "reset" > /proc/acpi/ibm/hotkey should do something non-useless,
so instead of setting it to Fn+F2, Fn+F3, Fn+F5, set it to
hotkey_recommended_mask.

It is not like it will survive for much longer, anyway.
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Len Brown <len.brown@intel.com>

Documentation/laptops/thinkpad-acpi.txt

@@ -219,7 +219,7 @@ The following commands can be written to the /proc/acpi/ibm/hotkey file:
 	echo 0xffffffff > /proc/acpi/ibm/hotkey -- enable all hot keys
 	echo 0 > /proc/acpi/ibm/hotkey -- disable all possible hot keys
 	... any other 8-hex-digit mask ...
-	echo reset > /proc/acpi/ibm/hotkey -- restore the original mask
+	echo reset > /proc/acpi/ibm/hotkey -- restore the recommended mask
 
 The following commands have been deprecated and will cause the kernel
 to log a warning:

drivers/platform/x86/thinkpad_acpi.c

@@ -3569,7 +3569,8 @@ static int hotkey_write(char *buf)
 			hotkey_enabledisable_warn(0);
 			res = -EPERM;
 		} else if (strlencmp(cmd, "reset") == 0) {
-			mask = hotkey_orig_mask;
+			mask = (hotkey_all_mask | hotkey_source_mask)
+				& ~hotkey_reserved_mask;
 		} else if (sscanf(cmd, "0x%x", &mask) == 1) {
 			/* mask set */
 		} else if (sscanf(cmd, "%x", &mask) == 1) {