dt: lpc32xx: pwm: correct LPC32xx PWM device node example

The change removes '0x' from a device node address and uses lower case
hex chars.

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>