esp_ptr_in_rtc_iram_fast logic should be executed if
SOC_RTC_FAST_MEM_SUPPORTED is set but it should also be executed
if IRAM and DRAM region mapping is the same. Remove the
SOC_RTC_IRAM_LOW != SOC_RTC_DRAM_LOW part of the check.
Update heap component to use the modify function appropriately.