Delete LLDB's code for getting / setting thread name.

This is now functionality in LLVM, and all callers have
already been updated to use the LLVM functions.

llvm-svn: 296946
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
index 9559df9..27d077e 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
@@ -72,7 +72,7 @@
     m_packets[idx].type = type;
     m_packets[idx].bytes_transmitted = bytes_transmitted;
     m_packets[idx].packet_idx = m_total_packet_count;
-    m_packets[idx].tid = Host::GetCurrentThreadID();
+    m_packets[idx].tid = llvm::get_threadid();
   }
 }
 
@@ -87,7 +87,7 @@
     m_packets[idx].type = type;
     m_packets[idx].bytes_transmitted = bytes_transmitted;
     m_packets[idx].packet_idx = m_total_packet_count;
-    m_packets[idx].tid = Host::GetCurrentThreadID();
+    m_packets[idx].tid = llvm::get_threadid();
   }
 }