Use labels instead of constants for HRAM

Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld

engine/menus/menu.asm

@@ -57,7 +57,7 @@ _InterpretMobileMenu::
 
 Draw2DMenu:
 	xor a
-	ld [hBGMapMode], a
+	ldh [hBGMapMode], a
 	call MenuBox
 	call Place2DMenuItemStrings
 	ret
@@ -249,17 +249,17 @@ _StaticMenuJoypad::
 _ScrollingMenuJoypad::
 	ld hl, w2DMenuFlags2
 	res 7, [hl]
-	ld a, [hBGMapMode]
+	ldh a, [hBGMapMode]
 	push af
 	call MenuJoypadLoop
 	pop af
-	ld [hBGMapMode], a
+	ldh [hBGMapMode], a
 	ret
 
 MobileMenuJoypad:
 	ld hl, w2DMenuFlags2
 	res 7, [hl]
-	ld a, [hBGMapMode]
+	ldh a, [hBGMapMode]
 	push af
 	call Move2DMenuCursor
 	call Do2DMenuRTCJoypad
@@ -267,7 +267,7 @@ MobileMenuJoypad:
 	call _2DMenuInterpretJoypad
 .skip_joypad
 	pop af
-	ld [hBGMapMode], a
+	ldh [hBGMapMode], a
 	call GetMenuJoypad
 	ld c, a
 	ret
@@ -331,15 +331,15 @@ MenuJoypadLoop:
 	ret
 
 .BGMap_OAM:
-	ld a, [hOAMUpdate]
+	ldh a, [hOAMUpdate]
 	push af
 	ld a, $1
-	ld [hOAMUpdate], a
+	ldh [hOAMUpdate], a
 	call WaitBGMap
 	pop af
-	ld [hOAMUpdate], a
+	ldh [hOAMUpdate], a
 	xor a
-	ld [hBGMapMode], a
+	ldh [hBGMapMode], a
 	ret
 
 Do2DMenuRTCJoypad:
@@ -555,10 +555,10 @@ Place2DMenuCursor:
 	ret
 
 _PushWindow::
-	ld a, [rSVBK]
+	ldh a, [rSVBK]
 	push af
 	ld a, BANK(wWindowStack)
-	ld [rSVBK], a
+	ldh [rSVBK], a
 
 	ld hl, wWindowStackPointer
 	ld e, [hl]
@@ -619,7 +619,7 @@ _PushWindow::
 	ld [hl], d
 
 	pop af
-	ld [rSVBK], a
+	ldh [rSVBK], a
 	ld hl, wWindowStackSize
 	inc [hl]
 	ret
@@ -655,12 +655,12 @@ _PushWindow::
 
 _ExitMenu::
 	xor a
-	ld [hBGMapMode], a
+	ldh [hBGMapMode], a
 
-	ld a, [rSVBK]
+	ldh a, [rSVBK]
 	push af
 	ld a, BANK(wWindowStack)
-	ld [rSVBK], a
+	ldh [rSVBK], a
 
 	call GetWindowStackTop
 	ld a, l
@@ -687,7 +687,7 @@ _ExitMenu::
 
 .done
 	pop af
-	ld [rSVBK], a
+	ldh [rSVBK], a
 	ld hl, wWindowStackSize
 	dec [hl]
 	ret