Build fixes on mbedtls and mqttc for CMake

[fdcavalcanti]

Summary

• crypto/mbedtls: expose include paths as public

Expose include paths as public when using CMake.

• netutils/mqttc: fix patch and add mbedtls dependency

Add mbedtls dependecy and fix patch path.

Apps mbedtls no longer appends its include directories to the global nuttx target (NUTTX_INCLUDE_DIRECTORIES / NUTTX_CXX_INCLUDE_DIRECTORIES). That global injection caused arch/vendor code (e.g. Espressif tf-psa-crypto) to pick up headers from nuttx-apps/crypto/mbedtls/mbedtls/include, which mixed two incompatible Mbed TLS trees and led to PSA/config include errors.

The post-FetchContent patch step used $(MQTTC_DIR) inside sh -c, which the shell treats as command substitution, not a CMake path. Replaced with a direct patch -d ${MQTTC_DIR} -p1 -i … invocation.
With mbedtls includes no longer global, MQTT-C with mbedtls wires nuttx_add_dependencies(TARGET mqttc DEPENDS mbedtls) when both CONFIG_NETUTILS_MQTTC_WITH_MBEDTLS and CONFIG_CRYPTO_MBEDTLS are set, and mqttc_mbedtls_pub lists mbedtls in DEPENDS so the example compiles against the same headers as the library.

This fixes build issues for Espressif devices whenever mbedtls was added (affecting CMake support only).

Impact

Impact on user: No.

Impact on build: Make builds are unaffected.
Anything that included <mbedtls/...> only because of those global includes, and does not get headers via:

• DEPENDS mbedtls / nuttx_add_dependencies(… mbedtls), or
• its own INCLUDE_DIRECTORIES / target_include_directories,
  could fail to compile until it gains an explicit dependency or include path. That is not vendor-specific; it depends on how each app’s CMakeLists.txt was written.

Impact on hardware: No.

Impact on documentation: No.

Impact on security: No.

Impact on compatibility: No.

Testing

Building

CMake build for esp32c3-devkit:wifi.
Append the following:

CONFIG_DEBUG_ASSERTIONS=y
CONFIG_DEBUG_ASSERTIONS_EXPRESSION=y
CONFIG_DEBUG_FEATURES=y
CONFIG_CRYPTO_MBEDTLS=y
CONFIG_MBEDTLS_APPS=y
CONFIG_MBEDTLS_APP_BENCHMARK=y
CONFIG_MBEDTLS_APP_SELFTEST=y
CONFIG_MBEDTLS_SELF_TEST=y
CONFIG_MBEDTLS_VERSION="3.6.2"
CONFIG_NETUTILS_MQTTC=y
CONFIG_NETUTILS_MQTTC_EXAMPLE=y
CONFIG_NETUTILS_MQTTC_WITH_MBEDTLS=y
CONFIG_NETUTILS_MQTTC_VERSION="1.1.5"
CONFIG_DEV_URANDOM=y

Results

CMake build would fail for this scenario, but works after the changes.

[cederom]

Thank you @fdcavalcanti :-)

[fdcavalcanti]

I see CI is complaining about the change, I'll investigate.

[simbit18]

@fdcavalcanti marked as a draft

[cederom]

Just to note build fixes required :-)

[simbit18]

Hi @fdcavalcanti, Perhaps it would be better to use function

nuttx_create_symlink

https://github.com/apache/nuttx/blob/master/cmake/nuttx_create_symlink.cmake