hw/battery: Add missing dependency to adc

battery_adc.c included adc/adc.h but package
for hw/drivers/adc was missing from dependency list.

Signed-off-by: Jerzy Kasenberg <jerzy@apache.org>

Author: kasjer

hw/battery/pkg.yml

@@ -23,6 +23,7 @@ pkg.keywords:
 
 pkg.deps:
     - "@apache-mynewt-core/kernel/os"
+    - "@apache-mynewt-core/hw/drivers/adc"
 
 pkg.req_apis:
     - console