New function, strtobytes(), allows k/M/G ISO size modifiers

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

src/util.h

@@ -39,6 +39,7 @@ extern char *prognm;
 #include <lite/conio.h>
 
 char *progname     (char *arg0);
+int   strtobytes   (char *arg);
 void  do_sleep     (unsigned int sec);
 
 long  jiffies      (void);