Update bootloader README and clean up makefile

code/boot/makefile

@@ -8,13 +8,14 @@
 # Project Defaults & Folders
 # ------------------------------------------------------------------------------
 
-TARGET  := boot
-TARGROM := $(TARGET).bin
-SRCDIR  := src/
+TARGET   := boot
+TARGREC  := $(TARGET).s19
+TARGROM  := $(TARGET).bin
+SRCDIR   := src/
 BUILDDIR := build/
-SRCS    := $(wildcard $(SRCDIR)*.s)
-OBJS    := $(patsubst $(SRCDIR)%.s,$(BUILDDIR)%.o,$(SRCS))
-INCS    := $(wildcard $(SRCDIR)*.inc)
+SRCS     := $(wildcard $(SRCDIR)*.s)
+OBJS     := $(patsubst $(SRCDIR)%.s,$(BUILDDIR)%.o,$(SRCS))
+INCS     := $(wildcard $(SRCDIR)*.inc)
 
 # ------------------------------------------------------------------------------
 # Toolchain Definitions
@@ -34,11 +35,11 @@ LDFLAGS := -f srec -m map.txt -s linkscript
 all: $(TARGROM)
 
 # Fix srec into flashable bin file
-$(TARGROM): $(TARGET).s19
+$(TARGROM): $(TARGREC)
 	$(FIX) -out $@ $<
 
 # Link objects
-$(TARGET).s19: $(OBJS)
+$(TARGREC): $(OBJS)
 	$(LD) $(LDFLAGS) -o $@ $^
 
 # Assemble objects
@@ -46,7 +47,6 @@ $(OBJS): $(BUILDDIR)%.o : $(SRCDIR)%.s
 	-@mkdir -p $(BUILDDIR)
 	$(AS) $(ASFLAGS) -o $@ $<
 
-.IGNORE: clean
 clean:
 	@echo 'Cleaning up intermediary files...'
-	@rm -rv $(TARGROM) $(TARGET).s19 map.txt $(BUILDDIR)
+	@rm -rv $(TARGROM) $(TARGREC) map.txt $(BUILDDIR)