Improve the state of handwritten assembly files (#865)

* Format all handwritten asm and document some

* Use c preprocessor for constants

* Fix

* Fix PI_STATUS_ERROR, some label improvements

* Avoid hi/lo for constants

* Some more comments

* Properly mark functions as functions and their sizes

* Fix merge

* Improvements

* Review suggestions, rework procedure start/end macros to be more like libreultra

* Move IPL3 symbol definitions into ipl3.s

* Fix undefined_syms, add include and language guards to asm.h and fix the comment in gbi.h

* Consistent hex capitalization, add some MIPS builtin defines to CC_CHECK to behave properly

* Add -no-pad-sections assembler option and clean up alignment in gu files and bzero

* Further suggestions and improvements

* Matrix conversion function clarifications

* Fix passing AVOID_UB to gcc

* Suggestions

* Suggestions, global interrupt mask improvements

* Further suggestions, interrupt mask comments

* Comments fixes, rdb.h

* Switch from # comments to // comments, remove unnecesary .set gp=64 directives

* Further review suggestions

* Missed one

src/code/main.c

@@ -46,7 +46,7 @@ void Main(void* arg) {
     osSyncPrintf("mainproc 実行開始\n"); // "Start running"
     gScreenWidth = SCREEN_WIDTH;
     gScreenHeight = SCREEN_HEIGHT;
-    gAppNmiBufferPtr = (PreNmiBuff*)osAppNmiBuffer;
+    gAppNmiBufferPtr = (PreNmiBuff*)osAppNMIBuffer;
     PreNmiBuff_Init(gAppNmiBufferPtr);
     Fault_Init();
     SysCfb_Init(0);