By adding external hook to sys_log we will allow applications
the flexibility of using various output mechanism such SPI,
flash, FS etc.
Jira: ZEP-1172
Change-Id: Ie32a5e52c3946ada0349b75a35cc107bb29385a1
Signed-off-by: Yossi Havusha <yossi.havusha@intel.com>
Signed-off-by: Anas Nashif <anas.nashif@intel.com>