Move __NR_shm* syscall numbers to x86-64 where they belong

The definitions are only correct for 64-bit Linux, not for 32-bit.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/arch/arch-x86.h b/arch/arch-x86.h
index 49e64dd..385a912 100644
--- a/arch/arch-x86.h
+++ b/arch/arch-x86.h
@@ -29,12 +29,6 @@
 #define __NR_sys_vmsplice	316
 #endif
 
-#ifndef __NR_shmget
-#define __NR_shmget 29
-#define __NR_shmat 30
-#define __NR_shmctl 31
-#endif
-
 #define	FIO_HUGE_PAGE		4194304
 
 #define nop		__asm__ __volatile__("rep;nop": : :"memory")
diff --git a/arch/arch-x86_64.h b/arch/arch-x86_64.h
index 8bdf01e..d7ea12e 100644
--- a/arch/arch-x86_64.h
+++ b/arch/arch-x86_64.h
@@ -29,6 +29,13 @@
 #define __NR_sys_vmsplice	278
 #endif
 
+#ifndef __NR_shmget
+#define __NR_shmget		 29
+#define __NR_shmat		 30
+#define __NR_shmctl		 31
+#define __NR_shmdt		 67
+#endif
+
 #define	FIO_HUGE_PAGE		2097152
 
 #define nop		__asm__ __volatile__("rep;nop": : :"memory")