ARM: dts: zynq: parallella: Fix up reserved-memory and memory nodes

[nathanrossi]

This pull request resolves issues where the reserved memory region is not available to the elink driver.

[    1.777966] elink 81000000.elink0: reserved-mem: failed requesting mem region
[    1.785062] elink 81000000.elink0: reserved mem probe failed
[    1.790665] elink 81000000.elink0: Failed parsing device tree
[    1.796490] elink: probe of 81000000.elink0 failed with error -12

With these changes the reserved memory is now available for request by the driver, and allows for the driver to probe correctly.

[    1.853077] epiphany elink0: elink: version field empty. Using default platform.
[    1.853095] epiphany elink0: Epiphany FPGA elink at address 0x81000000
[    1.853095] epiphany elink0: platform 01 revision 00

root@parallella:~# cat /proc/iomem
00000000-3dffffff : System RAM
  00208000-00e5bf37 : Kernel code
  00f64000-010b1b57 : Kernel data
3e000000-3fffffff : 81000000.elink0
80000000-8fffffff : 81000000.elink0
...

[olajep]

Thank you Nathan!