Fix Wasm translator to handle loop parameters on br_table default target.

Similar to an earlier issue for ordinary branches (fixed in PR #1833),
the cranelift-wasm crate did not previously correctly translate a
br_table instruction's default-target branch when the branch target was
a loop with loop parameters. The mistranslated CLIF resulted in a
validation error. This one-line fix simply fills in the correct
parameter count, generating a jump instruction with the appropriate
parameters from the stack.

This issue was found by :decoder in the SpiderMonkey embedding of
Cranelift, in https://bugzilla.mozilla.org/show_bug.cgi?id=1657062. The
test case is from that bug report.

cranelift/wasm/src/code_translator.rs

@@ -395,7 +395,7 @@ pub fn translate_operator<FE: FuncEnvironment + ?Sized>(
                 let i = state.control_stack.len() - 1 - (min_depth as usize);
                 let min_depth_frame = &state.control_stack[i];
                 if min_depth_frame.is_loop() {
-                    0
+                    min_depth_frame.num_param_values()
                 } else {
                     min_depth_frame.num_return_values()
                 }