Remove unused sections to avoid float issues

Avoids a linker error for `fmod` and `fmodf`. These functions are refenced in libcore. The KEEP ensures that the Multiboot section isn't removed.

Makefile

@@ -44,7 +44,7 @@ $(iso): $(kernel)
 	@rm -r build/isofiles
 
 $(kernel): cargo $(rust_os) $(assembly_object_files) $(linker_script)
-	@ld -n -T $(linker_script) -o $(kernel) $(assembly_object_files) $(rust_os)
+	@ld -n --gc-sections -T $(linker_script) -o $(kernel) $(assembly_object_files) $(rust_os)
 
 cargo:
 	@cargo build

src/arch/x86_64/linker.ld

@@ -22,7 +22,7 @@ SECTIONS {
   .boot :
   {
     /* ensure that the multiboot header is at the beginning */
-    *(.multiboot)
+    KEEP(*(.multiboot))
   }
 
   .text :