Build strings in libstdc++

[Peter Naulls]

I don't know if this is intentional, or some side effect of my build setup, but 
the OpenWrt 22.03 libstdc++ library has some build strings in it.

$ strings 
build_dir/target-mipsel_24kc_musl/root-ramips/usr/lib/libstdc++.so.6.0.29 | grep 
home

... /gcc-11.2.0/libstdc++-v3/src/c++11/debug.cc
... /gcc-11.2.0/libstdc++-v3/src/c++17/ryu/f2s_intrinsics.h


Etc, which was flagged as a security concern, especially since it contains
/home references.

C++ is no longer used in my setup in any case, so I removed it from the build.