arm64: update and align armreg.h with ARMv8.9 features

[harry.moulton_arm.com]

Summary

Update armreg.h to contain feature bit definitions for all architecture
versions up to and including ARMv8.9. This includes a number of
corrections for PAC_frac, PAN and ETS definitions.

Sponsored by: Arm Ltd
Signed-off-by: Harry Moulton <[e-mail]>

[andrew]

sys/arm64/include/armreg.h

1399–1400

1 is documented as also being not implemented (unlike previous versions of the Arm ARM)

1596–1619

Should we name the ID_AA64MMFR3_S*ERR_IMPL as ID_AA64MMFR3_S*ERR_ALL and ID_AA64MMFR3_A*ERR_IMPL as ID_AA64MMFR3_A*ERR_SOME? There are more values that indicate the presence of register fields, and how they can be used.

1823–1824

I try to keep the field in numeric order

[harry.moulton_arm.com]

sys/arm64/include/armreg.h

1399–1400

In this case then would we just leave it as _ETS_NONE, and not add the second "not implemented" field?

[andrew]

sys/arm64/include/armreg.h

1399–1400

In the unlikely case HW reports 1 here we will need to include it in the ETS table in identcpu.c so will need macros for both "not implemented" values. If not the kernel will report Unknown ETS(1).

[harry.moulton_arm.com]

Add definition for ETS 0b1 value, renamed S*ERR and A*ERR values, and re-ordered MTE_frac definitions.