daemon can not find possible compiler in ubuntu 20.04

[cyqw]

after install gcc by apt install in ubuntu 20.04
/usr/bin/gcc is a symlink file, the realpath of gcc is /usr/bin/x86_64-linux-gnu-gcc-9
the daemon can not find any compiler, because the bellow code skip symlink

  if (S_ISLNK(buf.st_mode)) {          // Symbolic link, ignore it.
    continue;
  }

yadcc/yadcc/daemon/cloud/compiler_registry.cc

Line 72 in 3f776f9

if (S_ISLNK(buf.st_mode)) { // Symbolic link, ignore it.

[0x804d8000]

Confirming. The same issue happens on Debian 11.

I'll fix this later.

[0x804d8000]

Fixed by #17 .