kernel: Add support for CFI (#2839)

Add basic support for the CFI value being passed in X18 since 11.0.0 by the official kernel.
We do not implement any random generator atm in the kernel and as such the KSystemControl.GenerateRandom function is stubbed

Ryujinx.HLE/HOS/Kernel/Common/KSystemControl.cs

@@ -58,6 +58,12 @@ namespace Ryujinx.HLE.HOS.Kernel.Common
             return DramMemoryMap.DramBase + GetDramSize(size);
         }
 
+        public static ulong GenerateRandom()
+        {
+            // TODO
+            return 0;
+        }
+
         public static ulong GetDramSize(MemorySize size)
         {
             return size switch

Ryujinx.HLE/HOS/Kernel/Threading/KThread.cs

@@ -187,6 +187,7 @@ namespace Ryujinx.HLE.HOS.Kernel.Threading
 
             if (is64Bits)
             {
+                Context.SetX(18, KSystemControl.GenerateRandom() | 1);
                 Context.SetX(31, stackTop);
             }
             else