ldgen: fix build issue on make when build dir is a symlink

Fixes an issue where build fails if the build directory is a symlink.
The issue is caused by the rule target and the final executable dependency
not matching.

Closes https://github.com/espressif/esp-idf/issues/3626

components/esp32/Makefile.projbuild

@@ -10,7 +10,7 @@ ifneq ("$(filter esp32,$(TEST_COMPONENTS_LIST))","")
 CPPFLAGS += -DESP_TIMER_DYNAMIC_OVERFLOW_VAL
 endif
 ESP32_LINKER_SCRIPT_TEMPLATE := $(COMPONENT_PATH)/ld/esp32.project.ld.in
-ESP32_LINKER_SCRIPT_OUTPUT_DIR := $(abspath $(BUILD_DIR_BASE)/esp32)
+ESP32_LINKER_SCRIPT_OUTPUT_DIR := $(realpath $(BUILD_DIR_BASE)/esp32)
 
 # Target to generate linker script generator from fragments presented by each of
 # the components