arch: add pkey and rseq syscall numbers everywhere

Most architectures define system call numbers for the rseq and pkey system
calls, even when they don't support the features, and perhaps never will.

Only a few architectures are missing these, so just define them anyway
for consistency. If we decide to add them later to one of these, the
system call numbers won't get out of sync then.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

arch/sparc/include/asm/unistd.h

@@ -59,9 +59,4 @@
 #define __IGNORE_getresgid
 #endif
 
-/* Sparc doesn't have protection keys. */
-#define __IGNORE_pkey_mprotect
-#define __IGNORE_pkey_alloc
-#define __IGNORE_pkey_free
-
 #endif /* _SPARC_UNISTD_H */