Remove unused lambda capture

This is a preparation CL to remove -Wno-unused-lambda-capture warning suppression.

Bug: chromium:681136
Change-Id: Iacd0933363cfe7e4a17191f83f567f2834dee6aa
Reviewed-on: https://chromium-review.googlesource.com/c/1288209
Commit-Queue: Takuto Ikuta <tikuta@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56754}

test/cctest/test-assembler-arm64.cc

@@ -6769,7 +6769,7 @@ static void LdrLiteralRangeHelper(size_t range, LiteralPoolEmitOutcome outcome,
   // can be handled by this test.
   CHECK_LE(code_size, range);
 
-  auto PoolSizeAt = [pool_entries](int pc_offset) {
+  auto PoolSizeAt = [](int pc_offset) {
     // To determine padding, consider the size of the prologue of the pool,
     // and the jump around the pool, which we always need.
     size_t prologue_size = 2 * kInstrSize + kInstrSize;