[wasm] Increase code space limit to 1024 MB

Liftoff increases code size, and people start deploying bigger modules.
Increase the wasm code space limit from 512 MB to 1024 MB to account
for this.

R=titzer@chromium.org

Bug: chromium:883639, chromium:872684
Change-Id: I3a2ca29d456635f7f3aa1daef5fa2b0249dc1645
Reviewed-on: https://chromium-review.googlesource.com/1226971
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56003}

src/globals.h

@@ -153,7 +153,7 @@ constexpr int kDoubleSizeLog2 = 3;
 // ARM64 only supports direct calls within a 128 MB range.
 constexpr size_t kMaxWasmCodeMemory = 128 * MB;
 #else
-constexpr size_t kMaxWasmCodeMemory = 512 * MB;
+constexpr size_t kMaxWasmCodeMemory = 1024 * MB;
 #endif
 
 #if V8_HOST_ARCH_64_BIT