arm64: dts: ti: k3-j721e-main: Fix supported max outbound regions

Cadence IP in J721E supports a maximum of 32 outbound regions. However
commit 4e583388 ("arm64: dts: ti: k3-j721e-main: Add PCIe device
tree nodes") incorrectly added this as 16 outbound regions. Now that
"cdns,max-outbound-regions" is an optional property with default value
as 32, remove "cdns,max-outbound-regions" from endpoint DT node.
(Since this doesn't impact existing functionality, it need not be
backported to older kernels).

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20210105151421.23237-2-kishon@ti.com