Change the order that the DarwinKernel DynamicLoader plugin uses
to search for kexts on the local system -- the ModuleList FindModule()
method is the best first attempt, only call
Symbols::DownloadObjectAndSymbolFile() if that has failed and this
is the kernel binary which really needs to have its symbols located.

<rdar://problem/13241893> 



git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@175495 91177308-0d34-0410-b5e6-96231b3b80d8
Fix a case where a kext module was being added to the Target
twice.


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@175496 91177308-0d34-0410-b5e6-96231b3b80d8