Fix addAtAddress ambiguous overloads

[JJL772]

Getting a lot of warnings like:

../cpsw_api_builder.h:97:23: warning: ‘virtual void IDev::addAtAddress(Field, unsigned int)’ was hidden [-Woverloaded-virtual=]
   97 |         virtual  void addAtAddress( Field f, unsigned nelms = DFLT_NELMS ) = 0;
      |                       ^~~~~~~~~~~~
../cpsw_api_builder.h:127:22: note:   by ‘virtual void IMMIODev::addAtAddress(Field, uint64_t, unsigned int, uint64_t, ByteOrder)’
  127 |         virtual void addAtAddress(Field child, uint64_t offset, unsigned nelms = DFLT_NELMS, uint64_t stride = DFLT_STRIDE, ByteOrder byteOrder = DFLT_BYTE_ORDER ) = 0;
      |                      ^~~~~~~~~~~~
../cpsw_api_builder.h:97:23: warning: ‘virtual void IDev::addAtAddress(Field, unsigned int)’ was hidden [-Woverloaded-virtual=]
   97 |         virtual  void addAtAddress( Field f, unsigned nelms = DFLT_NELMS ) = 0;
      |                       ^~~~~~~~~~~~
../cpsw_api_builder.h:140:33: note:   by ‘virtual void IMemDev::addAtAddress(Field, int)’
  140 |         virtual void            addAtAddress(Field child, int align = DFLT_ALIGN) = 0;
      |                                 ^~~~~~~~~~~~

This looks like a pretty big landmine since the only differentiating factor is signedness of the second argument. (int align vs unsigned nelms)

This could be resolved by either renaming the first method from virtual void addAtAddress( Field f, unsigned nelms = DFLT_NELMS ) to virtual void addArrayAtAddress( Field f, unsigned nelms = DFLT_NELMS ), or by changing the type of int align to something that isn't implicitly convertible to an integral type. For example, Align_t which has an explicit constructor taking int.

Both solutions will require an audit of modules using CPSW