TCF: update defaults to use configuration fragments
TCF: update defaults to use configuration fragments

Currently it plucks configuration strings in/out of the $O/.config and
that is quite dirty.

There is a cleaner way to do that with configuration fragments which
is now enabled by being able to include them from the object
directory.

Change-Id: Id51881391293ace89b58153c5de7db1afe67118a
Signed-off-by: Inaky Perez-Gonzalez <96af2f95d738a33e3cb28686ea74cc090643af9b@intel.com>

sharronliu/zephyr,galak/zephyr,aceofall/zephyr-iotos,runchip/zephyr-cc3220,bigdinotech/zephyr,holtmann/zephyr,zephyriot/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,fractalclone/zephyr-riscv,Vudentz/zephyr,pklazy/zephyr,rsalveti/zephyr,erwango/zephyr,sharronliu/zephyr,mbolivar/zephyr,erwango/zephyr,runchip/zephyr-cc3200,punitvara/zephyr,rsalveti/zephyr,fractalclone/zephyr-riscv,finikorg/zephyr,pklazy/zephyr,Vudentz/zephyr,nashif/zephyr,rsalveti/zephyr,fractalclone/zephyr-riscv,erwango/zephyr,bigdinotech/zephyr,sharronliu/zephyr,holtmann/zephyr,kraj/zephyr,fbsder/zephyr,kraj/zephyr,punitvara/zephyr,zephyriot/zephyr,runchip/zephyr-cc3200,fbsder/zephyr,bboozzoo/zephyr,finikorg/zephyr,ldts/zephyr,zephyrproject-rtos/zephyr,mbolivar/zephyr,GiulianoFranchetto/zephyr,fbsder/zephyr,erwango/zephyr,galak/zephyr,kraj/zephyr,mbolivar/zephyr,Vudentz/zephyr,finikorg/zephyr,GiulianoFranchetto/zephyr,ldts/zephyr,mbolivar/zephyr,holtmann/zephyr,aceofall/zephyr-iotos,pklazy/zephyr,ldts/zephyr,galak/zephyr,aceofall/zephyr-iotos,GiulianoFranchetto/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,rsalveti/zephyr,punitvara/zephyr,runchip/zephyr-cc3200,explora26/zephyr,punitvara/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,tidyjiang8/zephyr-doc,punitvara/zephyr,runchip/zephyr-cc3200,fbsder/zephyr,fbsder/zephyr,holtmann/zephyr,runchip/zephyr-cc3220,sharronliu/zephyr,explora26/zephyr,zephyrproject-rtos/zephyr,bboozzoo/zephyr,holtmann/zephyr,mbolivar/zephyr,explora26/zephyr,fractalclone/zephyr-riscv,galak/zephyr,ldts/zephyr,bboozzoo/zephyr,Vudentz/zephyr,bigdinotech/zephyr,bboozzoo/zephyr,finikorg/zephyr,tidyjiang8/zephyr-doc,nashif/zephyr,explora26/zephyr,ldts/zephyr,tidyjiang8/zephyr-doc,zephyriot/zephyr,aceofall/zephyr-iotos,runchip/zephyr-cc3220,Vudentz/zephyr,kraj/zephyr,runchip/zephyr-cc3220,zephyriot/zephyr,nashif/zephyr,bigdinotech/zephyr,pklazy/zephyr,erwango/zephyr,aceofall/zephyr-iotos,runchip/zephyr-cc3200,bboozzoo/zephyr,zephyriot/zephyr,fractalclone/zephyr-riscv,runchip/zephyr-cc3220,GiulianoFranchetto/zephyr,rsalveti/zephyr,nashif/zephyr,explora26/zephyr,Vudentz/zephyr,kraj/zephyr,bigdinotech/zephyr,pklazy/zephyr,tidyjiang8/zephyr-doc,sharronliu/zephyr,GiulianoFranchetto/zephyr,tidyjiang8/zephyr-doc