purgatory: fix disabling debug info

commit d83806c4c0 upstream.

Since 32ef9e5054, -Wa,-gdwarf-2 is no longer used in KBUILD_AFLAGS.
Instead, it includes -g, the appropriate -gdwarf-* flag, and also the
-Wa versions of both of those if building with Clang and GNU as.  As a
result, debug info was being generated for the purgatory objects, even
though the intention was that it not be.

Fixes: 32ef9e5054 ("Makefile.debug: re-enable debug info for .S files")
Signed-off-by: Alyssa Ross <hi@alyssa.is>
Cc: stable@vger.kernel.org
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/x86/purgatory/Makefile

@@ -64,8 +64,7 @@ CFLAGS_sha256.o			+= $(PURGATORY_CFLAGS)
 CFLAGS_REMOVE_string.o		+= $(PURGATORY_CFLAGS_REMOVE)
 CFLAGS_string.o			+= $(PURGATORY_CFLAGS)
 
-AFLAGS_REMOVE_setup-x86_$(BITS).o	+= -Wa,-gdwarf-2
-AFLAGS_REMOVE_entry64.o			+= -Wa,-gdwarf-2
+asflags-remove-y		+= -g -Wa,-gdwarf-2
 
 $(obj)/purgatory.ro: $(PURGATORY_OBJS) FORCE
 		$(call if_changed,ld)