seedrng: compress format strings with %s arguments

- Avoid an xstrdup call with seed_dir.
- Compress format strings with %s arguments.
- Open /dev/urandom for add entropy ioctl rather than /dev/random, so that
  /dev/random is only used for the already-sightly-flawed poll() check for
  creditability.

function                                             old     new   delta
seedrng_main                                         948     958     +10
seed_from_file_if_exists                             410     417      +7
.rodata                                           108338  108206    -132
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/1 up/down: 17/-132)          Total: -115 bytes
   text	   data	    bss	    dec	    hex	filename
 975829	   4227	   1816	 981872	  efb70	busybox_old
 975714	   4227	   1816	 981757	  efafd	busybox_unstripped

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
1 file changed