Commit for ticket #5755, issue https://github.com/ascom-au/ensurespeech-playbook/issues/11

files/patch.diff
* Added patch.diff file to patch dadh-dkms to fix compilation issue

tasks/dahdi.yml
* Added task to fix kernel version compilation issue with dahdi-dkms
* Added task to fix broken source file compilation issue with dahdi-dkms
* Added task to determine correct kernel version to use in compiling dahdi-dkms
* Updated asterisk-dahdi installation task to ignore and register dahdi-dkms compilation failure