arm: dts: imx93: fix pwm channel number for pwm-beeper

An incorrect pwm channel was set for pwm-beeper driver in device tree. As a result, a beeper device did not work.

This MR fixes this problem.

MR for Kernel: linux!148 (closed)

TBD: one issue is still open - a beeper does not react/click during reset. Will return to this problem later.