CMakeLists: prepare for Everest headers relocation

Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>
diff --git a/CMakeLists.txt b/CMakeLists.txt
index bda3977..84bed5a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -434,6 +434,14 @@
             DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/tests/include/test/test_keys.h)
         add_dependencies(mbedtls_test mbedtls_test_keys_header)
     endif()
+    # This is a dirty fix to allow mbedtls#10091 to be merged without psa#325.
+    # Once the latter will be merged, this can be simplified to just use
+    # the new path.
+    if(EXISTS "tf-psa-crypto/drivers/everest/include/tf-psa-crypto/private")
+        set(EVEREST_HEADERS_PATH "tf-psa-crypto/drivers/everest/include/tf-psa-crypto/private")
+    else()
+        set(EVEREST_HEADERS_PATH "tf-psa-crypto/drivers/everest/include")
+    endif()
     target_include_directories(mbedtls_test
         PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/tests/include
         PRIVATE ${MBEDTLS_FRAMEWORK_DIR}/tests/include
@@ -441,7 +449,7 @@
         PRIVATE include
         PRIVATE tf-psa-crypto/include
         PRIVATE tf-psa-crypto/drivers/builtin/include
-        PRIVATE tf-psa-crypto/drivers/everest/include/tf-psa-crypto/private/
+        PRIVATE ${EVEREST_HEADERS_PATH}
         PRIVATE library
         PRIVATE tf-psa-crypto/core
         PRIVATE tf-psa-crypto/drivers/builtin/src)
@@ -480,7 +488,7 @@
         PRIVATE library
         PRIVATE tf-psa-crypto/core
         PRIVATE tf-psa-crypto/drivers/builtin/src
-        PRIVATE tf-psa-crypto/drivers/everest/include/tf-psa-crypto/private/)
+        PRIVATE ${EVEREST_HEADERS_PATH})
 
     set_config_files_compile_definitions(mbedtls_test_helpers)
 endif()