x86/purgatory: Remove -nostdlib compiler flag

The -nostdlib option requests the compiler to not use the standard
system startup files or libraries when linking. It is effective only
when $(CC) is used as a linker driver.

$(LD) is directly used for linking purgatory.{ro,chk} here, hence
-nostdlib is unneeded.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20211107162641.324688-2-masahiroy@kernel.org

Author: masahir0y

arch/x86/purgatory/Makefile

@@ -16,7 +16,7 @@ CFLAGS_sha256.o := -D__DISABLE_EXPORTS
 
 # When linking purgatory.ro with -r unresolved symbols are not checked,
 # also link a purgatory.chk binary without -r to check for unresolved symbols.
-PURGATORY_LDFLAGS := -e purgatory_start -nostdlib -z nodefaultlib
+PURGATORY_LDFLAGS := -e purgatory_start -z nodefaultlib
 LDFLAGS_purgatory.ro := -r $(PURGATORY_LDFLAGS)
 LDFLAGS_purgatory.chk := $(PURGATORY_LDFLAGS)
 targets += purgatory.ro purgatory.chk