Convert nimble apps from log to modlog

Every sample nimble app used to register the `ble_hs_log` with the
console handler.

Now that the `ble_hs_log` doesn't exist, there is no need for apps to
register it.

Also, use the modlog package to write application log entries rather
than the log API.

apps/blemesh_shell/pkg.yml

@@ -26,6 +26,7 @@ pkg.deps:
     - "@apache-mynewt-core/kernel/os"
     - "@apache-mynewt-core/sys/console/full"
     - "@apache-mynewt-core/sys/log/full"
+    - "@apache-mynewt-core/sys/log/modlog"
     - "@apache-mynewt-core/sys/stats/full"
     - "@apache-mynewt-core/sys/shell"
     - nimble/controller

apps/blemesh_shell/src/main.c

@@ -99,8 +99,6 @@ main(void)
     sysinit();
 
     /* Initialize the NimBLE host configuration. */
-    log_register("ble_hs", &ble_hs_log, &log_console_handler, NULL,
-                 LOG_SYSLEVEL);
     ble_hs_cfg.reset_cb = blemesh_on_reset;
     ble_hs_cfg.sync_cb = blemesh_on_sync;
     ble_hs_cfg.store_status_cb = ble_store_util_status_rr;