Place common OpenOCD configs for the different cc13xx and cc26xx
families in boards/common/cc26xx_cc13xx/dist and automatically select
the correct one based on the (prefix of the) value of `$(CPU_MODEL)`, if
`OPENOCD_CONFIG` was not specified and no custom `openocd.cfg` is
located in the board's `dist` folder.
The `cc2650-launchpad` and `cc2650stk` have been adapted to use the
common config instead.
cpu/$(CPU)/Makefile.features and cpu/$(CPU)/Makefile.dep are
automatically included
Part of moving CPU/CPU_MODEL definition to Makefile.features to have it
available before Makefile.include.
Added additional support for the XDS100v3 debugger platform
Implemented default flash configuration for the XDS110 with support for XDS100v3 debugger with through DEBUGGER make flags