Properly decode architecture type in GDBRemoteCommunicationClient::GetCurrentProcessInfo.

Instead of forcing the remote arch type to MachO all the time, we
inspect the OS/vendor that the remote debug server reports and use it to
set the arch type to MachO, ELF or COFF accordingly.

See thread here for more context:
http://lists.cs.uiuc.edu/pipermail/lldb-commits/Week-of-Mon-20140915/012968.html

Change by Stephane Sezer.

Tested:
MacOSX 10.9.4 x86_64
Ubuntu 14.04 x86_64


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@217779 91177308-0d34-0410-b5e6-96231b3b80d8
Handle ARM ELF symbols properly: skip $t* and $a* symbols in ObjectFileELF.

ELF objects contain marker symbols to differentiate between ARM and
THUMB functions. Instead of storing them internally and having garbage
show up when symbols are searched for by the user, we can just skip them
and not store them at all, as we never actually need them.

Change by Stephane Sezer.

Tested:
Ubuntu 14.04 x86_64
MacOSX 10.9.4 x86_64


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@217782 91177308-0d34-0410-b5e6-96231b3b80d8