make_f2fs: specify sector size for target image size

am: 9a67c69e6c

Change-Id: I4e9f33855fbb88d56bb44911e87201d71d7604df

fs_mgr/fs_mgr_format.cpp

@@ -114,10 +114,19 @@ static int format_f2fs(char *fs_blkdev, uint64_t dev_sz, bool crypt_footer)
     }
 
     std::string size_str = std::to_string(dev_sz / 4096);
+    // clang-format off
     const char* const args[] = {
-        "/system/bin/make_f2fs", "-d1", "-f",
-        "-O", "encrypt", "-O", "quota",
-        fs_blkdev, size_str.c_str(), nullptr};
+        "/system/bin/make_f2fs",
+        "-d1",
+        "-f",
+        "-O", "encrypt",
+        "-O", "quota",
+        "-w", "4096",
+        fs_blkdev,
+        size_str.c_str(),
+        nullptr
+    };
+    // clang-format on
 
     return android_fork_execvp_ext(arraysize(args), const_cast<char**>(args), NULL, true,
                                    LOG_KLOG, true, nullptr, nullptr, 0);