[RFC] arm64: mm: use pgprot_device for device in phys_mem_access_prot

[Jisheng Zhang]

Hi all,

Normally, in arm64, kernel driver maps register space as device nGnRE. But
if we access the register space via. /dev/mem, then the mapping is
device nGnRnE, is there a mismatch here?

the fix is s/pgprot_noncached/pgprot_device in phys_mem_access_prot().

From armv8 ARM, this mismatch seems not the so called mismatched memory
attributes?

Thanks,
Jisheng