selftest/powerpc/ptrace/ptrace-pkey: Remove duplicate macros

./powerpc/ptrace/Makefile includes flags.mk.
In flags.mk, -I$(selfdir)/powerpc/include is
always included as part of CFLAGS. So it will
pick up the "pkeys.h" defined in powerpc/include.

ptrace-pkey.c test has macros defined which
are part of "pkeys.h" header file. Remove those
duplicates and include "pkeys.h"

Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20241216160257.87252-2-maddy@linux.ibm.com

tools/testing/selftests/powerpc/ptrace/ptrace-pkey.c

@@ -7,14 +7,7 @@
  */
 #include "ptrace.h"
 #include "child.h"
-
-#ifndef __NR_pkey_alloc
-#define __NR_pkey_alloc		384
-#endif
-
-#ifndef __NR_pkey_free
-#define __NR_pkey_free		385
-#endif
+#include "pkeys.h"
 
 #ifndef NT_PPC_PKEY
 #define NT_PPC_PKEY		0x110
@@ -61,11 +54,6 @@ struct shared_info {
 	unsigned long invalid_uamor;
 };
 
-static int sys_pkey_alloc(unsigned long flags, unsigned long init_access_rights)
-{
-	return syscall(__NR_pkey_alloc, flags, init_access_rights);
-}
-
 static int child(struct shared_info *info)
 {
 	unsigned long reg;