small build system and config files reorganization

c64/basic/init/initmsg_real.s

@@ -10,6 +10,8 @@ initmsg_real:
 	ldy #>startup_banner
 	jsr STROUT
 
+#if !CONFIG_BRAND_CUSTOM_BUILD
+
 	ldx #$01
 	ldy #$04
 	jsr plot_set
@@ -18,13 +20,23 @@ initmsg_real:
 	ldy #>rom_revision_basic_string
 	jsr STROUT
 
+#endif // no CONFIG_BRAND_CUSTOM_BUILD
+
+#if !CONFIG_BRAND_CUSTOM_BUILD
 	ldx #$03
+#else
+	ldx #$02
+#endif
 	ldy #$04
 	jsr plot_set
 
 	jsr initmsg_bytes_free
 
+#if !CONFIG_BRAND_CUSTOM_BUILD
 	ldx #$06
+#else
+	ldx #$05
+#endif
 	ldy #$00
 #if CONFIG_SHOW_PAL_NTSC && CONFIG_SHOW_FEATURES
 	jsr plot_set
@@ -54,6 +66,8 @@ initmsg_real:
 	ldy #>startup_banner
 	jsr STROUT
 
+#if !CONFIG_BRAND_CUSTOM_BUILD
+
 	ldx #$01
 	ldy #$0A
 	jsr plot_set
@@ -66,13 +80,23 @@ initmsg_real:
 	ldy #>rom_revision_basic_string
 	jsr STROUT
 
+#endif // no CONFIG_BRAND_CUSTOM_BUILD
+
+#if !CONFIG_BRAND_CUSTOM_BUILD
 	ldx #$03
+#else
+	ldx #$02
+#endif
 	ldy #$0A
 	jsr plot_set
 
 	jsr initmsg_bytes_free
 
+#if !CONFIG_BRAND_CUSTOM_BUILD
 	ldx #$06
+#else
+	ldx #$05
+#endif
 	ldy #$00
 #if CONFIG_SHOW_PAL_NTSC && CONFIG_SHOW_FEATURES
 	jsr plot_set

c64/basic/init/startup_banner.s

@@ -8,7 +8,10 @@
 
 .macro BANNER_TEXT() {
 
-#if CONFIG_BRAND_GENERIC
+#if CONFIG_BRAND_CUSTOM_BUILD
+	.text "OPEN ROMS "
+	.text CONFIG_CUSTOM_BRAND
+#elif CONFIG_BRAND_GENERIC
 	.text "OPEN ROMS GENERIC BUILD"
 #elif CONFIG_BRAND_TESTING
 	.text "OPEN ROMS TESTING BUILD"
@@ -61,11 +64,15 @@ rainbow_logo:
     .byte SET_COLOR_0, $00
 }
 
+#if !CONFIG_BRAND_CUSTOM_BUILD
+
 pre_revision_string:
 
 	.text "RELEASE "
 	.byte $00
 
+#endif // no CONFIG_BRAND_CUSTOM_BUILD
+
 #elif CONFIG_BANNER_BRAND && CONFIG_BRAND_MEGA_65
 
 	// Fancy Mega65 banner - from Retrofan