[PATCH] sparc: add missing comment about hyperprivileged register operands

[Jose E. Marchesi]

    > Hi.  Trivial patch adding some missing bits in that comment.
    > Ok to commit?
    
    Yes - this one counts as obvious.

Am I allowed to commit trivial/obvious patches like this without a
pre-approval, along with a [COMMITTED] email?
    
    > 2016-06-08  Jose E. Marchesi  <jose.marchesi@oracle.com>
    > 
    > 	* opcode/sparc.h: Add missing documentation for hyperprivileged
    > 	registers in rd (%) and rs1 ($).
    
    Approved - please apply.
    
Committed to master, thanks.