Remove unreachable else prongs

lib/std/zig/string_literal.zig

@@ -104,7 +104,6 @@ pub fn parse(
                     return error.InvalidCharacter;
                 },
             },
-            else => unreachable,
         }
     }
     unreachable;

src-self-hosted/translate_c.zig

@@ -2791,7 +2791,6 @@ fn transCharLiteral(
             "TODO: support character literal kind {}",
             .{kind},
         ),
-        else => unreachable,
     };
     if (suppress_as == .no_as) {
         return maybeSuppressResult(rp, scope, result_used, int_lit_node);

test/stage1/behavior/bugs/1111.zig

@@ -7,6 +7,5 @@ test "issue 1111 fixed" {
 
     switch (v) {
         Foo.Bar => return,
-        else => return,
     }
 }