This allow the tcc cross compilers to work as expected,
when tcc was build with '--enable-cross' and a simple config-extra.mak
(see the provided config-extra.mak.example).
Make sure, that cross development packages for libc are installed
Fixes also open bugs in various bug tracker. Example in debian: 940469
tcc: error: library 'c' not found
tcc: error: file 'crtn.o' not found
tcc: error: undefined symbol 'printf'
