[ESP32] encrypted_ota: Call abort API when aborting OTA and some refactoring (#28778)

* [ESP32] encrypted_ota: Call abort API when aborting and some refactoring

* Make DecryptEnd return an error and honour it

* Restyled by clang-format

---------

Co-authored-by: Restyled.io <commits@restyled.io>
diff --git a/src/platform/ESP32/OTAImageProcessorImpl.h b/src/platform/ESP32/OTAImageProcessorImpl.h
index 03e1367..4162711 100644
--- a/src/platform/ESP32/OTAImageProcessorImpl.h
+++ b/src/platform/ESP32/OTAImageProcessorImpl.h
@@ -67,7 +67,14 @@
     OTAImageHeaderParser mHeaderParser;
 
 #if CONFIG_ENABLE_ENCRYPTED_OTA
-    void EndDecryption();
+    CHIP_ERROR DecryptStart();
+    CHIP_ERROR DecryptEnd();
+    void DecryptAbort();
+
+    // This API decrypts the blockToDecrypt, dynamically allocates the memory for storing the
+    // plain text, and return that in decryptedBlock.
+    // Caller shall free the memory after use by calling free() on decryptedBlock.data()
+    CHIP_ERROR DecryptBlock(const ByteSpan & blockToDecrypt, ByteSpan & decryptedBlock);
 
     CharSpan mKey;
     bool mEncryptedOTAEnabled                 = false;