coding_guide: update cross-platform section
coding_guide: update cross-platform section

Change-Id: I6356951919e4e1a9cc81fa1025ed5fb565ea9705

dmerejkowsky/qibuild,aldebaran/qibuild,dmerejkowsky/qibuild,dmerejkowsky/qibuild,aldebaran/qibuild,dmerejkowsky/qibuild,dmerejkowsky/qibuild,aldebaran/qibuild,aldebaran/qibuild