Rework disassembly: out of makefile, separate sections, relocs (#1728)

* Rework disassembly: out of makefile, separate sections, relocs

* another nice print

* fix type hints for python 3.8 dinosaurs

* reencode from utf-8 to euc-jp (iconv) before assemble

* Add "include guards" to macro.inc

* For producing the expected file object files, assemble sections together instead of linking together the individually assembled sections

* review

* fixup

* require spimdisasm >=1.21.0

* remove assembling sections individually (for now)

* uppercase encoding names (standard)

include/macro.inc

@@ -1,3 +1,8 @@
+# Evaluate this file only once in case it's included more than once
+.ifndef _MACRO_INC_GUARD
+.internal _MACRO_INC_GUARD
+.set _MACRO_INC_GUARD, 1
+
 .macro glabel label
     .global \label
     \label:
@@ -47,3 +52,5 @@
 .set $fs4f,         $f29
 .set $fs5,          $f30
 .set $fs5f,         $f31
+
+.endif