While preparing a new system for development, `./configure` reaches a point
where it fails with:
```
$ ./configure
dracut needs fts development files.
```
After installing the fts library, `./configure` keeps throwing the same error:
```
$ rpm -qf /usr/include/fts.h
glibc-devel-2.38-6.1.x86_64
$ ./configure
dracut needs fts development files.
```
The problem is `${CC} $CFLAGS $LDFLAGS conftest.c` can also fail if the compiler
referenced by `$CC` is not installed.
exit 1
fi
+if ! command -v "${CC}" > /dev/null; then
+ echo "dracut needs a C compiler (${CC} not found)." >&2
+ exit 1
+fi
+
cat << EOF > conftest.c
#include <fts.h>
int main() {