Quieten multiply warning

We no longer gate multiply with the valid signal, so it's complaining
a lot. Comment out the warning.

Signed-off-by: Anton Blanchard <anton@linux.ibm.com>

multiply.vhdl

@@ -78,7 +78,7 @@ begin
 		when OP_MUL_H64 =>
 			d2 := d(127 downto 64);
 		when others =>
-			report "Illegal insn type in multiplier";
+			--report "Illegal insn type in multiplier";
 			d2 := (others => '0');
 		end case;