Crossgen Requires -JITPath Parameter

[brianrob]

From dotnet/cli#3223 it appears that crossgen now requires the -JITPath parameter.

@gkhanna79, can you provide details on this change and what is needed? Perfcollect calls crossgen to generate perfmap files for tracing, and it sounds like it will be broken by this change.

[gkhanna79]

crossgen needs to be invoked by passing the JITPath parameter to point to the absolute file path for clrjit.dll OR clrjit.dll needs to be next to crossgen.exe.

[brianrob]

Thanks @gkhanna79.