Refactored a handful of things in tests

- Now test errors have correct line reporting! #line directives
  are passed to the compiler that reference the relevant line in
  the test case shell script.

  --- Multi-block directory ---
  ./tests/test_dirs.sh:109: assert failed with 0, expected 1
      lfs_unmount(&lfs) => 1

- Cleaned up the number of implicit global variables provided to
  tests. A lot of these were infrequently used and made it difficult
  to remember what was provided. This isn't an MCU, so there's very
  little cost to stack allocations when needed.

- Minimized the results.py script (previously stats.py) output to
  match minimization of test output.

emubd/lfs_emubd.c

@@ -197,7 +197,7 @@ int lfs_emubd_read(const struct lfs_config *cfg, lfs_block_t block,
         }
     }
 
-    emu->stats.read_count += 1;
+    emu->stats.read_count += size;
     LFS_TRACE("lfs_emubd_read -> %d", 0);
     return 0;
 }
@@ -270,7 +270,7 @@ int lfs_emubd_prog(const struct lfs_config *cfg, lfs_block_t block,
         emu->history.blocks[0] = block;
     }
 
-    emu->stats.prog_count += 1;
+    emu->stats.prog_count += size;
     LFS_TRACE("lfs_emubd_prog -> %d", 0);
     return 0;
 }
@@ -317,7 +317,7 @@ int lfs_emubd_erase(const struct lfs_config *cfg, lfs_block_t block) {
         }
     }
 
-    emu->stats.erase_count += 1;
+    emu->stats.erase_count += cfg->block_size;
     LFS_TRACE("lfs_emubd_erase -> %d", 0);
     return 0;
 }