Fix warnings in gas/config/tc-s390.c

[Nick Clifton]

Hi Andreas,

> 2001-08-25  Andreas Jaeger  <aj@suse.de>
> 
> 	* config/tc-s390.c: Add missing prototypes
> 	(md_gather_operands): Make static.

Approved.

Cheers
        Nick

PS.  Thanks for all these patches.