x86: Correct segment permission flags in 64-bit linker script

While these don't get actively used (afaict), it still doesn't hurt
for them to properly reflect what how respective segments will get
mapped/ accessed.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
LKML-Reference: <4AA0E95F0200007800013707@vpn.id2.novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/vmlinux.lds.S

@@ -45,9 +45,9 @@ PHDRS {
 	text PT_LOAD FLAGS(5);          /* R_E */
 	data PT_LOAD FLAGS(7);          /* RWE */
 #ifdef CONFIG_X86_64
-	user PT_LOAD FLAGS(7);          /* RWE */
+	user PT_LOAD FLAGS(5);          /* R_E */
 #ifdef CONFIG_SMP
-	percpu PT_LOAD FLAGS(7);        /* RWE */
+	percpu PT_LOAD FLAGS(6);        /* RW_ */
 #endif
 	init PT_LOAD FLAGS(7);          /* RWE */
 #endif