[fastcall] Remove redundant offsetof comparison

This fixes a compilation error on GCC.

Bug: v8:12072
Change-Id: Ief14968ba15776ad5f72b85b93c9158996833453
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3086475
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Auto-Submit: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#76227}

include/v8-fast-api-calls.h

@@ -317,12 +317,6 @@ struct FastApiTypedArray : public FastApiTypedArrayBase {
 #ifdef DEBUG
     ValidateIndex(index);
 #endif  // DEBUG
-    static_assert(offsetof(FastApiTypedArray<T>, length_) <
-                      offsetof(FastApiTypedArray<T>, data_),
-                  "length_ should be "
-                  "stored in memory before data_, initializing the "
-                  "FastApiTypedArray struct will fail.");
-
     T tmp;
     memcpy(&tmp, reinterpret_cast<T*>(data_) + index, sizeof(T));
     return tmp;