Fix lowering issue in x64 vany_true: sinking and using original value. (#4815)

The x64 lowring of `vany_true` both sinks mergeable loads and uses the
original register. This PR fixes the lowering to force the value into a
register first. Ideally we should solve the issue by catching this in
the ISLE type system, as described in #4745, but this resolves the issue
for now.

Fixes #4807.

tests/misc_testsuite/simd/issue4807.wast

@@ -0,0 +1,8 @@
+ (module
+  (func (result i32)
+    global.get 0
+    v128.any_true
+  )
+  (global (;0;) (mut v128) v128.const i64x2 0 0)
+)
+