Add option to build gdbserver for target that does not require libstdc++.so

[nyetwurk]

Workaround for issue #753

Before:

# ldd /usr/bin/gdbserver 
        libdl.so.2 => /lib/libdl.so.2 (0x400dc000)
        libstdc++.so.6 => /lib/libstdc++.so.6 (0x400ef000)
        libm.so.6 => /lib/libm.so.6 (0x4027c000)
        libgcc_s.so.1 => /lib/libgcc_s.so.1 (0x4007b000)
        libc.so.6 => /lib/libc.so.6 (0x40341000)
        /lib/ld-linux.so.3 (0x4004a000)

After:

# ldd /usr/bin/gdbserver
        libdl.so.2 => /lib/libdl.so.2 (0x401e0000)
        libm.so.6 => /lib/libm.so.6 (0x400f7000)
        libgcc_s.so.1 => /lib/libgcc_s.so.1 (0x401f3000)
        libc.so.6 => /lib/libc.so.6 (0x40223000)
        /lib/ld-linux.so.3 (0x400c4000)