GATT: put include declarations before characteristics in service

BT spec Version 5.0 | Vol 3, Part G 3.1:
"All include definitions shall immediately follow the service
declaration and precede any characteristic definitions."

Bug: 78107486
Change-Id: Ifb61864d30fed450a73cd71c60b4e85666ae1458
(cherry picked from commit b163ff5168330966fc1ba5dae45114a55feef2c7)