#548 [PATCH] Do not call arc4random_stir or arc4random_addrandom when they are not available

[Xin LI]

arc4random_stir should not be called directly (it's fully automated after FreeBSD r227520, or approximately FreeBSD_version 1000002), the interface will be removed soon (FreeBSD bug 230756).

[Raphael Manfredi]

Should be fixed by commit 7a4a2dacfe545b11ab5c414a1f03edfa80b33021.