misc: vexpress: Off by one in vexpress_syscfg_exec()

The > comparison should be >= to prevent reading beyond the end of the
func->template[] array.

(The func->template array is allocated in vexpress_syscfg_regmap_init()
and it has func->num_templates elements.)

Fixes: 974cc7b9

 ("mfd: vexpress: Define the device as MFD cells")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>