some work towards extra keys support in MEGA65 mode

src/kernal/keyboard/kb_matrix.s

@@ -56,7 +56,7 @@ __kb_matrix_ctrl:
 	.byte $1F,$19,$07,$9E,$02,$08,$15,$16
 	.byte $12,$09,$0A,$92,$0D,$0B,$0F,$0E
 #if CONFIG_EDIT_TABULATORS
-	.byte $00,$10,$0C,$00,KEY_TAB_FW,$1B,$00,KEY_TAB_BW
+	.byte $00,$10,$0C,$00,KEY_C64_TAB_FW,$1B,$00,KEY_C64_TAB_BW
 #else
 	.byte $00,$10,$0C,$00,$00,$1B,$00,$00
 #endif

src/kernal/keyboard/kb_matrix_128.s

@@ -16,7 +16,7 @@
 
 kb_matrix_128:
 
-	.byte KEY_HELP,$38,$35,KEY_TAB_FW,$32,$34,$37,$31
+	.byte KEY_HELP,$38,$35,KEY_C64_TAB_FW,$32,$34,$37,$31
 	.byte KEY_ESC,$2B,$2D,$8D,$0D,$36,$39,$33
 	.byte $00,$30,$2E,$91,$11,$9D,$1D,$00
 

src/kernal/keyboard/kb_matrix_65.s

@@ -15,11 +15,11 @@
 
 kb_matrix_65:
 
-	.byte $00, KEY_TAB_FW, $00, KEY_HELP, KEY_F9,  KEY_F11, KEY_F13, KEY_ESC
+	.byte $00, KEY_C64_TAB_FW, $00, KEY_HELP, KEY_F9,  KEY_F11, KEY_F13, KEY_ESC
 
 kb_matrix_65_shifted:
 
-	.byte $00, KEY_TAB_BW, $00, KEY_HELP, KEY_F10, KEY_F12, KEY_F14, KEY_ESC
+	.byte $00, KEY_C64_TAB_BW, $00, KEY_HELP, KEY_F10, KEY_F12, KEY_F14, KEY_ESC
 
 
 #endif // CONFIG_KEYBOARD_C65 and no CONFIG_LEGACY_SCNKEY

src/kernal/keyboard/scnkey.s

@@ -428,12 +428,12 @@ scnkey_got_petscii:
 	// Special handling for SHIFT+TAB; it is easier than creating new matrix
 
 	tax
-	cmp #KEY_TAB_FW
+	cmp #KEY_C64_TAB_FW
 	bne !+
 	lda SHFLAG
 	and #KEY_FLAG_SHIFT
 	beq !+
-	ldx #KEY_TAB_BW
+	ldx #KEY_C64_TAB_BW
 !:
 	txa