mfd: tqmx86: Fix a typo in MODULE_DESCRIPTION

Based on the file name and code of the driver, it is likely that this
module is related to TQMx86 and not TQx86.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>