Add a switch to PerfView to disable NGEN Pdb generation for .NET Core assemblies using CrossGen

[safihamid]

We will need to do a merge for our prod profiles and there is no crossgen.exe available on the VMs and we get lots of log entries like below:

NGEN PDB creation for C:\Program Files\dotnet\shared\Microsoft.NETCore.App\8.0.7\System.Linq.dll took 0.00 Sec
Could not find CLR directory for NGEN image C:\Program Files\dotnet\shared\Microsoft.NETCore.App\8.0.7\System.Collections.Immutable.dll, Trying .NET Core
Checking for CoreCLR case, looking for CrossGen at C:\Program Files\dotnet\shared\Microsoft.NETCore.App\8.0.7\crossGen.exe
Found coreclr: at C:\Program Files\dotnet\shared\Microsoft.NETCore.App\8.0.7\coreclr.dll, timestamp 6/13/2024 7:34:54 PM
Could not find crossgen, giving up
Could not find Crossgen.exe to generate PDBs, giving up.