Reunbreak the MEM_ENCRYPT build

[Matthew Wilcox <willy@infradead.org>]

Current top of tree doesn't build for me:

../arch/x86/include/asm/mem_encrypt.h:23:20: error: static declaration of ‘mem_encrypt_init’ follows non-static declaration
   23 | static inline void mem_encrypt_init(void) { }
      |                    ^~~~~~~~~~~~~~~~
In file included from ../include/linux/printk.h:6,
                 from ../include/linux/kernel.h:30,
                 from ../arch/x86/include/asm/percpu.h:27,
                 from ../arch/x86/include/asm/preempt.h:6:
../include/linux/init.h:158:6: note: previous declaration of ‘mem_encrypt_init’ with type ‘void(void)’
  158 | void mem_encrypt_init(void);
      |      ^~~~~~~~~~~~~~~~

I applied this locally:

diff --git a/include/linux/init.h b/include/linux/init.h
index 1200fa99e848..266c3e1640d4 100644
--- a/include/linux/init.h
+++ b/include/linux/init.h
@@ -155,7 +155,6 @@ void __init init_rootfs(void);

 void init_IRQ(void);
 void time_init(void);
-void mem_encrypt_init(void);
 void poking_init(void);
 void pgtable_cache_init(void);

Probably this is the wrong fix.