idf_size.py: Fix issue where diram size was halved in cases where iram was not fully filled with cache

This fixes an attempted fix for diram size calculation where it was counted twice, however the fix did not account for cases where iram was not fully filled with cache and therefore was of non 0 size.
Now the calculation should be correct regardless of the cache size.

Closes espressif/esp-idf#9960

Author: DNedic

tools/idf_size.py

@@ -584,13 +584,17 @@ def in_iram(x: MemRegions.Region) -> bool:
         r = StructureForSummary()
 
         diram_filter = filter(in_diram, segments)
-        r.diram_total = int(get_size(diram_filter) / 2)
+        r.diram_total = get_size(diram_filter)
 
         dram_filter = filter(in_dram, segments)
         r.dram_total = get_size(dram_filter)
         iram_filter = filter(in_iram, segments)
         r.iram_total = get_size(iram_filter)
 
+        # This fixes counting the diram twice if the cache fills the iram entirely
+        if r.iram_total == 0:
+            r.diram_total //= 2
+
         def filter_in_section(sections: Iterable[MemRegions.Region], section_to_check: str) -> List[MemRegions.Region]:
             return list(filter(lambda x: LinkingSections.in_section(x.section, section_to_check), sections))  # type: ignore