arm64: zynqmp: Fix opp-table-cpu

arm64: zynqmp: Fix opp-table-cpu

OPP table name now should start with "opp-table" and OPP entries
shouldn't contain commas and @ signs in accordance to the new schema
requirement.

The same change was done in Linux by commit c6d4a8977598 ("ARM: tegra:
Rename CPU and EMC OPP table device-tree nodes"), commit ffbe853a3f5a
("ARM: dts: sunxi: Fix OPPs node name") or commit b7072cc5704d ("arm64:
dts: qcom: qcs404: Rename CPU and CPR OPP tables").

Signed-off-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/a1176349448df35127dbac15c1eeb2229505bae7.1652262769.git.michal.simek@amd.com