x64: cpu_detect: Add detection of waitpkg instructions

waitpkg introduces 3 instructions, UMONITOR, UMWAIT and TPAUSE.

src/common/x64/cpu_detect.cpp

@@ -144,6 +144,7 @@ static CPUCaps Detect() {
             caps.bmi2 = Common::Bit<8>(cpu_id[1]);
             caps.sha = Common::Bit<29>(cpu_id[1]);
 
+            caps.waitpkg = Common::Bit<5>(cpu_id[2]);
             caps.gfni = Common::Bit<8>(cpu_id[2]);
 
             __cpuidex(cpu_id, 0x00000007, 0x00000001);

src/common/x64/cpu_detect.h

@@ -67,6 +67,7 @@ struct CPUCaps {
     bool pclmulqdq : 1;
     bool popcnt : 1;
     bool sha : 1;
+    bool waitpkg : 1;
 };
 
 /**