android: Fix const to non-const issue on android-tester
android: Fix const to non-const issue on android-tester

According to definition from hardware/bluetooth.h, the "val" field does
not have const modifier.

Fix clang errors like:

android/android-tester.c:760:14: error: initializing 'void *' with an
expression of type 'const char (*)[18]' discards qualifiers
[-Werror,-Wincompatible-pointer-types-discards-qualifiers]

pkarasev3/bluez,silent-snowman/bluez,mapfau/bluez,ComputeCycles/bluez,ComputeCycles/bluez,silent-snowman/bluez,ComputeCycles/bluez,pstglia/external-bluetooth-bluez,pkarasev3/bluez,ComputeCycles/bluez,silent-snowman/bluez,mapfau/bluez,silent-snowman/bluez,pkarasev3/bluez,pkarasev3/bluez,pstglia/external-bluetooth-bluez,pstglia/external-bluetooth-bluez,pstglia/external-bluetooth-bluez,mapfau/bluez,mapfau/bluez