[ptr-compr] Enable 32-bit smis on non-ptr-compr builds

This will help detecting TaggedIndex-related issues earlier.

Bug: v8:10047
Change-Id: Ibd150e8ff77ec807977e0ee1b54c880620840bac
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2071261
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66527}

BUILD.gn

@@ -107,7 +107,7 @@ declare_args() {
 
   # Enable pointer compression (sets -dV8_COMPRESS_POINTERS).
   v8_enable_pointer_compression = ""
-  v8_enable_31bit_smis_on_64bit_arch = true
+  v8_enable_31bit_smis_on_64bit_arch = false
 
   # Sets -dOBJECT_PRINT.
   v8_enable_object_print = ""