remove or1k version of sem.h

It's identical to the generic version, after evaluating the endian
preprocessor checks in the generic version.

arch/or1k/bits/sem.h

@@ -1,11 +0,0 @@
-struct semid_ds {
-	struct ipc_perm sem_perm;
-	time_t sem_otime;
-	time_t __unused1;
-	time_t sem_ctime;
-	time_t __unused2;
-	char __sem_nsems_pad[sizeof(time_t)-sizeof(short)];
-	unsigned short sem_nsems;
-	time_t __unused3;
-	time_t __unused4;
-};