generic syscalls: kill cruft from removed pkey syscalls

pkey_set() and pkey_get() were syscalls present in older versions
of the protection keys patches.  They were fully excised from the
x86 code, but some cruft was left in the generic syscall code.  The
C++ comments were intended to help to make it more glaring to me to
fix them before actually submitting them.  That technique worked,
but later than I would have liked.

I test-compiled this for arm64.

Fixes: a60f7b69 ("generic syscalls: Wire up memory protection keys syscalls")
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Cc: linux-arch@vger.kernel.org
Cc: mgorman@techsingularity.net
Cc: linux-api@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: luto@kernel.org
Cc: akpm@linux-foundation.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/syscalls.h

@@ -902,8 +902,5 @@ asmlinkage long sys_pkey_mprotect(unsigned long start, size_t len,
 				  unsigned long prot, int pkey);
 asmlinkage long sys_pkey_alloc(unsigned long flags, unsigned long init_val);
 asmlinkage long sys_pkey_free(int pkey);
-//asmlinkage long sys_pkey_get(int pkey, unsigned long flags);
-//asmlinkage long sys_pkey_set(int pkey, unsigned long access_rights,
-//			     unsigned long flags);
 
 #endif

include/uapi/asm-generic/unistd.h

@@ -730,10 +730,6 @@ __SYSCALL(__NR_pkey_mprotect, sys_pkey_mprotect)
 __SYSCALL(__NR_pkey_alloc,    sys_pkey_alloc)
 #define __NR_pkey_free 290
 __SYSCALL(__NR_pkey_free,     sys_pkey_free)
-#define __NR_pkey_get 291
-//__SYSCALL(__NR_pkey_get,      sys_pkey_get)
-#define __NR_pkey_set 292
-//__SYSCALL(__NR_pkey_set,      sys_pkey_set)
 
 #undef __NR_syscalls
 #define __NR_syscalls 291