esp_tool: Exclude elf-sha256 from bootloader

Closes: IDFGH-690

components/esptool_py/Makefile.projbuild

@@ -39,7 +39,9 @@ endif
 endif
 endif
 
+ifndef IS_BOOTLOADER_BUILD
 ESPTOOL_ELF2IMAGE_OPTIONS += --elf-sha256-offset 0xb0
+endif
 
 ESPTOOLPY_WRITE_FLASH=$(ESPTOOLPY_SERIAL) write_flash $(if $(CONFIG_ESPTOOLPY_COMPRESSED),-z,-u) $(ESPTOOL_WRITE_FLASH_OPTIONS)
 

components/esptool_py/project_include.cmake

@@ -52,7 +52,9 @@ if(CONFIG_SECURE_BOOT_ENABLED AND
         ${ESPTOOLPY_ELF2IMAGE_FLASH_OPTIONS} --secure-pad)
 endif()
 
-set(ESPTOOLPY_ELF2IMAGE_OPTIONS --elf-sha256-offset 0xb0)
+if(NOT BOOTLOADER_BUILD)
+    set(ESPTOOLPY_ELF2IMAGE_OPTIONS --elf-sha256-offset 0xb0)
+endif()
 
 if(CONFIG_ESPTOOLPY_FLASHSIZE_DETECT)
     # Set ESPFLASHSIZE to 'detect' *after* elf2image options are generated,