Update the checks in EmulateInstructionARM::GetFramePointerRegisterNumber 
and EmulateInstructionARM::GetFramePointerDWARFRegisterNumber to recognize
the Apple arm convention (of using r7 for the frame pointer, regardless of
thumb or arm) even if the OS does not match Darwin/MacOSX/iOS.  Also 
corrects the behavior for thumb code on non-Apple platforms.
<rdar://problem/14661537> 


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@198648 91177308-0d34-0410-b5e6-96231b3b80d8