Fix most compiler warnings in the boot and code segments (#674)

* Less warnings in boot & code segments

* few more warnings gone

* Ran formatter

* z_view warning gone

* -> 1

* f31 -> 31

* Remove function casts

* Few more small improvements

* Separate declaration and assignment in func_80091738 and Item_Give

Co-authored-by: Thar0 <maximilianc64@gmail.com>

src/code/TwoHeadArena.c

@@ -78,6 +78,7 @@ void* THA_GetTail(TwoHeadArena* tha) {
 
 void* THA_AllocStart(TwoHeadArena* tha, u32 size) {
     void* start = tha->head;
+
     tha->head = (u32)tha->head + size;
     return start;
 }