soc/intel_adsp: Remove dead bootloader framework

Now that the IMR boot code is built as part of the main Zephyr
executable, remove the old stuff and its directory.  The C file
becomes "boot.c" in the common directory and the two
bootloader-specific headers move into common/include.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
10 files changed