update_engine: update another read size

fix another type conversion error on 32 bit systems.

Bug: 361048795
Test: th
Change-Id: I4541595c53a60696329a8927f98afa965edb0c0a
diff --git a/payload_consumer/filesystem_verifier_action.cc b/payload_consumer/filesystem_verifier_action.cc
index 93e61bf..2934fb7 100644
--- a/payload_consumer/filesystem_verifier_action.cc
+++ b/payload_consumer/filesystem_verifier_action.cc
@@ -319,7 +319,7 @@
     return;
   }
   const auto read_size =
-      std::min<size_t>(buffer_size, end_offset - start_offset);
+      std::min<uint64_t>(buffer_size, end_offset - start_offset);
   const auto bytes_read = fd->Read(buffer, read_size);
   if (bytes_read < 0 || static_cast<size_t>(bytes_read) != read_size) {
     PLOG(ERROR) << "Failed to read offset " << start_offset << " expected "