Revert "cpu: add HPDS, LOR, PAN detection for arm64"

This reverts CL 704075.

Reason for revert: Based on golang/go#76386, it doesn't seem to work correctly.

Fixes golang/go#76386.

Change-Id: I51ccbc8715c25c0d061d56dfbf0e8158f1207018
Reviewed-on: https://go-review.googlesource.com/c/sys/+/724160
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Auto-Submit: Cherry Mui <cherryyz@google.com>

cpu/cpu.go

@@ -92,9 +92,6 @@ var ARM64 struct {
 	HasSHA2     bool // SHA2 hardware implementation
 	HasCRC32    bool // CRC32 hardware implementation
 	HasATOMICS  bool // Atomic memory operation instruction set
-	HasHPDS     bool // Hierarchical permission disables in translations tables
-	HasLOR      bool // Limited ordering regions
-	HasPAN      bool // Privileged access never
 	HasFPHP     bool // Half precision floating-point instruction set
 	HasASIMDHP  bool // Advanced SIMD half precision instruction set
 	HasCPUID    bool // CPUID identification scheme registers