[PATCH v9 1/7] arm64: cpufeature: Detect CPU RAS Extentions

From: Xie XiuQi ARM's v8.2 Extentions add support for Reliability, Availability and Serviceability (RAS). On CPUs with these extensions system software can use additional barriers to isolate errors and determine if faults are pending. Add cpufeature detection and a barrier

[PATCH v9 1/7] arm64: cpufeature: Detect CPU RAS Extentions

From: Xie XiuQi ARM's v8.2 Extentions add support for Reliability, Availability and Serviceability (RAS). On CPUs with these extensions system software can use additional barriers to isolate errors and determine if faults are pending. Add cpufeature detection and a barrier in the context-switch