cmd: Fix license command

The license command isn't usually built and has a few problems:
- The rules to generate license.h haven't worked in a long time,
  re-write these based on the bmp_logo.h rules.
- 'tok' is unused and the license text size has increased
- bin2header.c wasn't grabbing unistd.h to know the prototype for
  read().

Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Tom Rini <trini@konsulko.com>

tools/bin2header.c

@@ -8,6 +8,7 @@
 
 #include <stdlib.h>
 #include <stdio.h>
+#include <unistd.h>
 
 int main(int argc, char **argv)
 {