powerpc: Add PVN support for HeXin C2000 processor

mainline inclusion
from mainline-v6.8-rc1
commit e12d8e2602d2bcd26022eff3e2519d25925e760c
category: other
bugzilla: https://gitee.com/openeuler/kernel/issues/I8ZMAY

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v6.8-rc1&id=e12d8e2602d2bcd26022eff3e2519d25925e760c



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HeXin Tech Co. has applied for a new PVN from the OpenPower Community
for its new processor C2000. The OpenPower has assigned a new PVN
and this newly assigned PVN is 0x0066, add pvr register related
support for this PVN.

Signed-off-by: Zhao Ke <ke.zhao@shingroup.cn>
Link: https://discuss.openpower.foundation/t/how-to-get-a-new-pvr-for-processors-follow-power-isa/477/10


Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231129075845.57976-1-ke.zhao@shingroup.cn


Signed-off-by: Ren Zhijie <zhijie.ren@shingroup.cn>