Revert wrong commit "work on INS support for MEGA65 mode"

This reverts commit 2c5e181457.

src/kernal/screen_m65/mega65_chrout_screen_control_2.s

@@ -40,84 +40,19 @@ m65_chrout_screen_SHIFT_OFF:
 	sta MODE
 	jmp_8 m65_chrout_screen_ctrl2_end
 
-// STOP key
 
-m65_chrout_screen_STOP:
+// GFX/TXT switching support
 
-	lda #$00
-	sta QTSW
-	sta INSRT
+m65_chrout_screen_GFX:
+
+	lda VIC_YMCSB
+	and #$02 // to upper case
+!:
+	sta VIC_YMCSB
 	jmp_8 m65_chrout_screen_ctrl2_end
 
-// INS key
+m65_chrout_screen_TXT:
 
-m65_chrout_screen_INS:
-
-	// First prepare the pointer to the current row
-
-	jsr m65_helper_scrlpnt_color
-	jsr m65_helper_scrlpnt_to_screen
-
-	// Check for windowed mode
-
-	lda M65_SCRWINMODE
-	bmi_16 m65_chrout_screen_INS_winmode
-
-	// Check if last character of the line is space
-
-	ldy M65_SCRMODE
-	lda m65_scrtab_txtwidth,y
-	dec_a
-	taz
-	lda_lp (M65_LPNT_SCR), z
-	cmp #$20
-	bne_16 m65_chrout_screen_ctrl2_end
-	phz
-
-	// Last character is space - move the characters
-
-	jsr m65_chrout_screen_INS_copy
-
-	// Store space in the current character cell
-
-	lda #$20
-	sta_lp (M65_LPNT_SCR), z
-
-	// Move the color memory
-
-	jsr m65_helper_scrlpnt_color
-	plz
-	jsr m65_chrout_screen_INS_copy
-
-	// Store current colour in the current character cell
-
-	lda COLOR
-	and #$0F
-	sta_lp (M65_LPNT_SCR), z
-
-	// Increase insert mode count (which causes quote-mode like behaviour) and quit
-	
-	inc INSRT
-	jmp_8 m65_chrout_screen_ctrl2_end
-
-m65_chrout_screen_INS_winmode:
-
-	// Check if last character of the line within window is space
-
-	// XXX provide implementation
-
-	jmp_8 m65_chrout_screen_ctrl2_end
-
-
-
-m65_chrout_screen_INS_copy:
-
-	dez
-	lda_lp (M65_LPNT_SCR), z
-	inz
-	sta_lp (M65_LPNT_SCR), z
-	dez
-	cpz M65__TXTCOL
-	bne m65_chrout_screen_INS_copy
-
-	rts
+	lda VIC_YMCSB
+	ora #$02    // to lower case
+	bne !-      // branch always