stdio: enable dprintf() and vdprintf()

src/libc/stdio/printf/print.c

@@ -2,6 +2,7 @@
 #include <ctype.h>
 #include <stdint.h>
 #include <string.h>
+#include <unistd.h>
 #include <fxlibc/printf.h>
 
 /* Internal buffer, used when no buffer is specified for output */
@@ -111,7 +112,7 @@ void __printf_flush(struct __printf_output *out)
 	/* File pointer: output with write */
 	else if(out->fd)
 	{
-		// write(fd, out->buffer, out->ptr - out->buffer);
+		write(out->fd, out->buffer, out->ptr - out->buffer);
 	}
 
 	/* Switch to the internal buffer (when writing to a string that string