1. Change all the hash used from the coap module to generated by the bluedroid module directly.
component/bt: Added the <string.h> include file to the gattc_co module to avoid compile error.
1. add the L1 include path with a prefix, such like osi/list.h, stack/a2d_api.h and etc.
2. modify component, only bluedroid/api/include/api is export to another component and application,
other include path just for bluedroid used
3. put bluedroid/include into common/include/common, so the root directory of bluedroid have no include path.
4. modify doxygen to use esp_bt.h and redirect to
component/bt/bluedroid/api/include/api/
fix compile
