arm64: dts: imx8qm: Remove adma pwm

arm64: dts: imx8qm: Remove adma pwm

There is no adma pwm on iMX8QM, so remove it from the DT. When enabled,
this cause warnings on resource partition ownership check by U-Boot
that receives messages from SCU firmware saying that these resources are
not owned:

Booting using the fdt blob at 0x9d400000
Loading Device Tree to 00000000fd622000, end 00000000fd66efff ... OK
Disable pwm@5a190000 rsrc 188 not owned
Disable clock-controller@5a590000 rsrc 188 not owned

Signed-off-by: Andrejs Cainikovs <andrejs.cainikovs@toradex.com>
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>