This provides the basic infrastructure to load kernel-specific python
helper scripts when debugging the kernel in gdb.

The loading mechanism is based on gdb loading for -gdb.py when
opening . Therefore, this places a corresponding link to the
main helper script into the output directory that contains vmlinux.

The main scripts will pull in submodules containing Linux specific gdb
commands and functions. To avoid polluting the source directory with
compiled python modules, we link to them from the object directory.

Due to gdb.parse_and_eval and string redirection for gdb.execute, we
depend on gdb >= 7.2.

This feature is enabled via CONFIG_GDB_SCRIPTS.

Signed-off-by: Jan Kiszka
Acked-by: Michal Marek [kbuild stuff]
Cc: Thomas Gleixner
Cc: Jason Wessel
Cc: Andi Kleen
Cc: Ben Widawsky
Cc: Borislav Petkov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds