staging: unisys: uislib: uisqueue.c: rewrite of do_locked_client_insert

1) removed unused variables
2) fixed sparse warning of context imbalance in 'do_locked_client_insert'
                         different lock contexts for basic block
3) removed the call to visor_signalqueue_empty() , this function is
   checking whether a signal queue is empty, but the return value
   of the function is not beeing used, so it is safe to remove.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>