gas: improve architecture mismatch diagnostics in sparc
    
    Merely dumping the mnemonic name in "architecture mismatch" errors may
    not provide enough information to determine what went wrong, as the same
    mnemonic can be used for different variants of an instruction pertaining
    to different architecture levels.
    
    This little patch makes the assembler to include the instruction
    arguments in the error message.
    
    gas/ChangeLog:
    
    2016-09-14  Jose E. Marchesi  <jose.marchesi@oracle.com>
    
    	* config/tc-sparc.c (sparc_ip): Print the instruction arguments
    	in "architecture mismatch" error messages.