Replaced instances of string.size() with string.empty()

tsk/pool/apfs_pool_compat.cpp

@@ -185,7 +185,7 @@ uint8_t APFSPoolCompat::poolstat(FILE *hFile) const noexcept try {
                                    vol.changed() % 1000000000, time_buf));
 
     const auto unmount_log = vol.unmount_log();
-    if (unmount_log.size() != 0) {
+    if (!unmount_log.empty()) {
       tsk_fprintf(hFile, "|\n");
       tsk_fprintf(hFile, "|   Unmount Logs\n");
       tsk_fprintf(hFile, "|   ------------\n");

tsk/pool/tsk_pool.hpp

@@ -44,7 +44,7 @@ class TSKPool {
   inline uint32_t dev_block_size() const noexcept { return _dev_block_size; }
   inline uint64_t num_blocks() const noexcept { return _num_blocks; }
   inline uint64_t first_img_offset() const noexcept {
-      if (_members.size() >= 1) {
+      if (!_members.empty()) {
           return _members[0].second;
       }
       return 0;