Make MD5 check configurable via Kconfig

CMakeLists.txt

@@ -46,6 +46,6 @@ else()
 
 endif()
 
-if(DEFINED MD5_ENABLED)
-    target_compile_definitions(${target} PRIVATE -DMD5_ENABLED=${MD5_ENABLED})
+if(DEFINED MD5_ENABLED OR CONFIG_SERIAL_FLASHER_MD5_ENABLED)
+    target_compile_definitions(${target} PUBLIC -DMD5_ENABLED=1)
 endif()

Kconfig

@@ -0,0 +1,7 @@
+menu "ESP serial flasher"
+    config SERIAL_FLASHER_MD5_ENABLED
+        bool "Enable MD5 check"
+        default y
+        help
+            Select this option to enable MD5 hashsum check after flashing.
+endmenu