Add support for stackprotector -strong

Needs patched gcc48 or gcc49.

Signed-off-by: David Sterba <dsterba@suse.cz>
Refresh patches

Conflict stackprotector and grsec:
- dropped hunk
+      depends on X86_64 || !PAX_MEMORY_UDEREF

orig: arch/x86/Kconfig
new:  arch/Kconfig

Signed-off-by: David Sterba <dsterba@suse.cz>
Enable CONFIG_CC_STACKPROTECTOR_STRONG

Signed-off-by: David Sterba <dsterba@suse.cz>