build: LOG_TAG consistency, include order, build fixes

Fix the order of includes across a bunch of files, and declare LOG_TAG
at the top of every file in which it is used.

Consistently use bt_ as a LOG_TAG prefix.
Fix issues with LOG macro usage.
Remove unused includes and double-includes (when in related .h)

Add includes as necessary to compile cleanly (problems surfaced by
reordering includes)

Change-Id: Ic55520c8302b06bbc1942c10c448b20844669da6
diff --git a/service/gatt_server.cpp b/service/gatt_server.cpp
index 3abdff9..40db111 100644
--- a/service/gatt_server.cpp
+++ b/service/gatt_server.cpp
@@ -13,6 +13,9 @@
 //  See the License for the specific language governing permissions and
 //  limitations under the License.
 //
+
+#define LOG_TAG "bt_gatts"
+
 #include "gatt_server.h"
 
 #include <stdio.h>
@@ -30,13 +33,11 @@
 #include <unordered_map>
 #include <vector>
 
-#define LOG_TAG "bt_gatt_server"
-#include "osi/include/log.h"
-
 #include "core_stack.h"
 #include "hardware/bluetooth.h"
 #include "hardware/bt_gatt.h"
 #include "logging_helpers.h"
+#include "osi/include/log.h"
 #include "osi/include/osi.h"
 #include "uuid.h"