staging: brcm80211: remove extern variable definitions in bcmsrom.c

The file bcmsrom.c defined two global externals. As these were also
not used these have been removed.
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Reviewed-by: Roland Vossen <rvossen@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/brcm80211/brcmsmac/bcmsrom.c

@@ -64,8 +64,6 @@ typedef struct varbuf {
 	char *buf;		/* pointer to current position */
 	unsigned int size;	/* current (residual) size in bytes */
 } varbuf_t;
-extern char *_vars;
-extern uint _varsz;
 
 /* Assumptions:
  * - Ethernet address spans across 3 consective words