Use variables for build and pepperk and rename build target.

Instead of hardcoding the names set them using a variable.
Also rename the target build to the name of the file it builds which is
in the ELFFILE variable.

Makefile

@@ -1,3 +1,6 @@
+
+BUILDDIR := build
+ELFFILE := pepperk
 SOURCES = src/sched/spinlock.c src/debug/misc.c src/io/term/flanterm_backends/fb.c src/io/term/flanterm.c src/debug/panic.c src/debug/stacktrace.c src/boot/boot.c src/sched/scheduler.c src/sched/process.c src/mem/heap/kheap.c src/mem/paging/vmm.c src/mem/paging/paging.c src/mem/paging/pmm.c src/string/string.c src/io/kbd/ps2.c src/io/serial/serial.c src/io/term/term.c src/idt/idt.c src/mem/gdt/gdt.c src/mem/misc/utils.c src/time/timer.c src/kmain.c
 
 CC := x86_64-elf-gcc
@@ -8,17 +11,17 @@ LD := x86_64-elf-ld
 
 .PHONY: build build-iso debug debug2 run clean
 
-build:
-	mkdir -p build
-	rm -f *.o build/*.o
+$(ELFFILE):
+	mkdir -p $(BUILDDIR)
+	rm -f *.o $(BUILDDIR)/*.o
 	$(CC) -g -c -Isrc $(SOURCES) $(CC_PROBLEMATIC_FLAGS) $(CC_FLAGS)
-	mv *.o build/
-	nasm -f elf64 src/idt/idt.S -o build/idt_stub.o
-	$(LD) -o pepperk -T linker.ld build/*.o
-	nm -n pepperk | awk '$$2 ~ /[TtDdBbRr]/ {print $$1, $$3}' > symbols.map
+	mv *.o $(BUILDDIR)/
+	nasm -f elf64 src/idt/idt.S -o $(BUILDDIR)/idt_stub.o
+	$(LD) -o $(ELFFILE) -T linker.ld $(BUILDDIR)/*.o
+	nm -n $(ELFFILE) | awk '$$2 ~ /[TtDdBbRr]/ {print $$1, $$3}' > symbols.map
 	python3 symbols.py
-	nasm -f elf64 symbols.S -o build/symbols.o
-	$(LD) -o pepperk -T linker.ld build/*.o
+	nasm -f elf64 symbols.S -o $(BUILDDIR)/symbols.o
+	$(LD) -o $(ELFFILE) -T linker.ld $(BUILDDIR)/*.o
 
 limine/limine:
 	rm -rf limine
@@ -28,7 +31,7 @@ limine/limine:
 build-iso: limine/limine build
 	rm -rf iso_root
 	mkdir -p iso_root/boot
-	cp -v pepperk iso_root/boot
+	cp -v $(ELFFILE) iso_root/boot
 	mkdir -p iso_root/boot/limine
 	cp -v limine.conf iso_root/boot/limine
 	mkdir -p iso_root/EFI/BOOT
@@ -44,14 +47,14 @@ build-iso: limine/limine build
 
 debug:
 	/usr/bin/qemu-system-x86_64 -drive file=pepper.iso -s -S -d int -D qemu.log -no-reboot -no-shutdown &
-	gdb pepperk --command=debug.gdb
+	gdb $(ELFFILE) --command=debug.gdb
 
 debug2:
 	/usr/bin/qemu-system-x86_64 -drive file=pepper.iso -s -S -d int -no-reboot -no-shutdown &
-	pwndbg pepperk --command=debug.gdb
+	pwndbg $(ELFFILE) --command=debug.gdb
 
 run: build-iso
 	/usr/bin/qemu-system-x86_64 -cdrom pepper.iso -serial stdio
 
 clean:
-	rm -rf *.o symbols.map symbols.S pepperk iso_root pepper.iso limine build/*.o
+	rm -rf *.o symbols.map symbols.S $(ELFFILE) iso_root pepper.iso limine $(BUILDDIR)/*.o