test/mesh: fix `sbc_encoder.h not found` by including ./3rd-party/bludroid/*

[theshteves]

The Problem

[  0%] Building C object CMakeFiles/btstack.dir/pico/pico-sdk/lib/btstack/3rd-party/micro-ecc/uECC.c.o
[  1%] Building C object CMakeFiles/btstack.dir/pico/pico-sdk/lib/btstack/example/sco_demo_util.c.o
In file included from /pico/pico-sdk/lib/btstack/example/sco_demo_util.c:53:
/pico/pico-sdk/lib/btstack/test/mesh/../../src/classic/btstack_sbc_bluedroid.h:45:10: fatal error: 'sbc_encoder.h' file not found
#include "sbc_encoder.h"
         ^~~~~~~~~~~~~~~
1 error generated.
make[2]: *** [CMakeFiles/btstack.dir/pico/pico-sdk/lib/btstack/example/sco_demo_util.c.o] Error 1
make[1]: *** [CMakeFiles/btstack.dir/all] Error 2
make: *** [all] Error 2

The Solution

Include ./3rd-party/bludroid/* (see diff)

[mringwal]

Thanks. Are you interested in using our mesh implementation?