[lldb] Ignore swig warnings about shadowed overloads (#83317)

This specifically addresses the warnings:
$LLVM/lldb/include/lldb/API/SBCommandReturnObject.h:119: Warning 509:
Overloaded method lldb::SBCommandReturnObject::PutCString(char const *)
effectively ignored,
$LLVM/lldb/include/lldb/API/SBCommandReturnObject.h:119: Warning 509: as
it is shadowed by lldb::SBCommandReturnObject::PutCString(char const
*,int).

There is exactly one declaration of SBCommandReturnObject::PutCString.
The second parameter (of type `int`) has default value `-1`. Without
investigating why SWIG believes there are 2 method declarations, I
believe it is safe to ignore this warning. It does not appear to
actually impact functionality in any way.

rdar://117744660