Added distribution info to ArchSpec and qHostInfo message.

ArchSpec now contains an optional distribution_id, with getters and
setters. Host::GetArchitecture () sets it on non-Apple platforms using
Host::GetDistributionId (). The distribution_id is ignored during
ArchSpec comparisons.

The gdb remote qHostInfo message transmits it, if set, via the
distribution_id={id-value} key/value pair. Updated gdb remote docs to
reflect this change.

As before, GetDistributionId () returns nothing on non-Linux platforms
at this time. On Linux, it is returned only if the lsb_platform
command is installed (in /bin or /usr/bin), and only if the
distributor id key is returned by 'lsb_platform -i'. This id is
lowercased, and whitespace is replaced with underscores.

llvm-svn: 199539
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.cpp
index 9579e7c..bed8852 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.cpp
@@ -313,6 +313,14 @@
     response.PutCStringAsRawHex8(host_triple.getTriple().c_str());
     response.Printf (";ptrsize:%u;",host_arch.GetAddressByteSize());
 
+    const char* distribution_id = host_arch.GetDistributionId ().AsCString ();
+    if (distribution_id)
+    {
+        response.PutCString("distribution_id:");
+        response.PutCStringAsRawHex8(distribution_id);
+        response.PutCString(";");
+    }
+
     uint32_t cpu = host_arch.GetMachOCPUType();
     uint32_t sub = host_arch.GetMachOCPUSubType();
     if (cpu != LLDB_INVALID_CPUTYPE)