Before this, a copy constructor declared as in the following snippet was
not being treated as a copy constructor.

class A
{
public:
  A (A &); // OK.
  A (const A &); // Not being treated as a copy constructor because of the
                 // 'const' qualifier.
};

gdb/ChangeLog:

2014-09-11  Siva Chandra Reddy  <sivachandra@google.com>

        PR c++/13403
        PR c++/15154
        * gdbtypes.c (make_qualified_type): Make non-static.
        * gdbtypes.h (make_qualified_type): Declare.
        * gnu-v3-abi.c (gnuv3_pass_by_reference): Lookup copy
        constructors with qualified args