[nrf toup] cmake: fix dependency for merged files to sign

It is required to depend on both the wrapper target and the file.
This patch adds the missing file dependency.
Prior to this signed.hex (and following files) were not updated
upon code change.

Signed-off-by: Håkon Øye Amundsen <[email protected]>

Author: hakonfam

zephyr/CMakeLists.txt

@@ -23,7 +23,7 @@ if(CONFIG_BOOTLOADER_MCUBOOT)
   set(merged_hex_file
     ${app_binary_dir}/mcuboot_primary_app.hex)
   set(merged_hex_file_depends
-    mcuboot_primary_app_hex)
+    mcuboot_primary_app_hex$<SEMICOLON>${PROJECT_BINARY_DIR}/mcuboot_primary_app.hex)
   set(sign_merged
     $<TARGET_EXISTS:partition_manager>)
   set(to_sign_hex