Makefile.inc: Add aliases for submodule updates to gitconfig target

Updating submodules seem to give people headaches, so this adds a pair
of git aliases to update them.

'git sup' updates the submodules to the latest versions, but leaves any
locally modified files.

'git sup-destroy' will remove the current submodules and re-initialize
them.  This deletes any local changes.

Change-Id: Id62a30d88b3b6d285b3f00555d7609509aa1561f
Signed-off-by: Martin Roth <martinroth@google.com>
Reviewed-on: https://review.coreboot.org/16573
Tested-by: build bot (Jenkins)
Reviewed-by: Omar Pakker
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
1 file changed