lib/inflate.c: remove dead code

This is a follow up from a discussion in Xen:

The if-statement tests that `res` is non-zero; meaning the case zero is
never reached.

Link: https://lore.kernel.org/all/[email protected]/
Link: https://lkml.kernel.org/r/[email protected]
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Ariel Otilibili <[email protected]>
Suggested-by: Jan Beulich <[email protected]>
Cc: Andrew Cooper <[email protected]>
Cc: Anthony PERARD <[email protected]>
Cc: Michal Orzel <[email protected]>
Cc: Julien Grall <[email protected]>
Cc: Roger Pau Monné <[email protected]>
Cc: Stefano Stabellini <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

lib/inflate.c

@@ -1257,8 +1257,6 @@ static int INIT gunzip(void)
     /* Decompress */
     if ((res = inflate())) {
 	    switch (res) {
-	    case 0:
-		    break;
 	    case 1:
 		    error("invalid compressed format (err=1)");
 		    break;