pw_status: Update Status::CODE to Status::Code()

- Update Status::CODE style to Status::Code() using
  pw_status/update_style.py.
- Make minor adjustments to the pw_assert tests to get them passing.

Change-Id: Ie54c3c605178fd1e42c7cedbcff324115f3ed279
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/19165
Commit-Queue: Wyatt Hepler <hepler@google.com>
Reviewed-by: Ewout van Bekkum <ewout@google.com>
diff --git a/pw_kvs/public/pw_kvs/flash_memory.h b/pw_kvs/public/pw_kvs/flash_memory.h
index a486889..029fba2 100644
--- a/pw_kvs/public/pw_kvs/flash_memory.h
+++ b/pw_kvs/public/pw_kvs/flash_memory.h
@@ -59,7 +59,7 @@
 
   virtual bool IsEnabled() const = 0;
 
-  virtual Status SelfTest() { return Status::UNIMPLEMENTED; }
+  virtual Status SelfTest() { return Status::Unimplemented(); }
 
   // Erase num_sectors starting at a given address. Blocking call.
   // Address should be on a sector boundary. Returns:
@@ -199,7 +199,7 @@
   virtual ~FlashPartition() = default;
 
   // Performs any required partition or flash-level initialization.
-  virtual Status Init() { return Status::OK; }
+  virtual Status Init() { return Status::Ok(); }
 
   // Erase num_sectors starting at a given address. Blocking call.
   // Address must be on a sector boundary. Returns: