fix(build): fix build failure if CMAKE_EXECUTABLE_SUFFIX is set

From: Arno Moonen <arno.moonen@airios.eu>

Follows original message from Arno Moonen <arno.moonen@airios.eu>

While integrating the ESP-IDF into our existing CMake structure,
I've come across quite some hurdles. Most I've been able to fix
in our CMake files, however this one I could not.

Most of the targets created by the esptool_py component assume
that the EXECUTABLE IDF build property (which contains the name
of the CMake executable target) always equals the name of the
created binary.

This is however not always true. For instance, in our setup we use
CMAKE_EXECUTABLE_SUFFIX_C and CMAKE_EXECUTABLE_SUFFIX_CXX in our
toolchain file (both set to .elf). If we do add_executable(my_app),
the target binary file would actually be my_app.elf.

In order to fix this, I've updated it to use the TARGET_FILE generated
expression. That way we also no longer need the EXECUTABLE_DIR IDF build
property here.

I've fixed this on v5.0.1 (as that's the ESP-IDF version I'm currently
trying to integrate), but I assume it should be easy to apply the same
fix to newer versions and the master branch as well.

Note that this problem might exist in multiple places where EXECUTABLE
is being used. While going through the ESP-IDF code base, I even noticed
that a few places actually already seem to use the TARGET_FILE expression.
To be honest the property name might be somewhat confusing as well, as it
is actually the executable target.

Closes #12558

components/esptool_py/project_include.cmake

@@ -109,7 +109,6 @@ idf_build_get_property(build_dir BUILD_DIR)
 
 idf_build_get_property(elf_name EXECUTABLE_NAME GENERATOR_EXPRESSION)
 idf_build_get_property(elf EXECUTABLE GENERATOR_EXPRESSION)
-idf_build_get_property(elf_dir EXECUTABLE_DIR GENERATOR_EXPRESSION)
 
 if(CONFIG_SECURE_BOOT_BUILD_SIGNED_BINARIES AND NOT BOOTLOADER_BUILD)
     set(unsigned_project_binary "${elf_name}-unsigned.bin")
@@ -125,10 +124,10 @@ set(PROJECT_BIN "${elf_name}.bin")
 if(CONFIG_APP_BUILD_GENERATE_BINARIES)
     add_custom_command(OUTPUT "${build_dir}/.bin_timestamp"
         COMMAND ${ESPTOOLPY} elf2image ${esptool_elf2image_args}
-            -o "${build_dir}/${unsigned_project_binary}" "${elf_dir}/${elf}"
+            -o "${build_dir}/${unsigned_project_binary}" "$<TARGET_FILE:$<GENEX_EVAL:${elf}>>"
         COMMAND ${CMAKE_COMMAND} -E echo "Generated ${build_dir}/${unsigned_project_binary}"
         COMMAND ${CMAKE_COMMAND} -E md5sum "${build_dir}/${unsigned_project_binary}" > "${build_dir}/.bin_timestamp"
-        DEPENDS ${elf}
+        DEPENDS "$<TARGET_FILE:$<GENEX_EVAL:${elf}>>"
         VERBATIM
         WORKING_DIRECTORY ${build_dir}
         COMMENT "Generating binary image from built executable"
@@ -200,7 +199,7 @@ add_custom_target(monitor
     COMMAND ${CMAKE_COMMAND}
     -D "IDF_PATH=${idf_path}"
     -D "SERIAL_TOOL=${ESPMONITOR}"
-    -D "SERIAL_TOOL_ARGS=--target;${target};${monitor_rev_args};${elf_dir}/${elf}"
+    -D "SERIAL_TOOL_ARGS=--target;${target};${monitor_rev_args};$<TARGET_FILE:$<GENEX_EVAL:${elf}>>"
     -D "WORKING_DIRECTORY=${build_dir}"
     -P run_serial_tool.cmake
     WORKING_DIRECTORY ${CMAKE_CURRENT_LIST_DIR}