ARM: dts: Update pcie ranges for dra7

In order to update pcie to probe with ti-sysc and genpd, let's update the
pcie ranges to not use address 0 for 0x20000000 and 0x30000000. The range
for 0 is typically used for child devices as the offset from the module
base. In the following patches, we will update pcie to probe with ti-sysc,
and the patches become a bit confusing to read compared to other similar
modules unless we update the ranges first. So let's just use the full
addresses for ranges for the 0x20000000 and 0x30000000 ranges.

Tested-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>