[S390] Remove last P390 trace.

Seems like I forgot this hunk...
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

include/asm-s390/setup.h

@@ -65,7 +65,6 @@ extern unsigned long machine_flags;
 
 #define MACHINE_FLAG_VM		(1UL << 0)
 #define MACHINE_FLAG_IEEE	(1UL << 1)
-#define MACHINE_FLAG_P390	(1UL << 2)
 #define MACHINE_FLAG_CSP	(1UL << 3)
 #define MACHINE_FLAG_MVPG	(1UL << 4)
 #define MACHINE_FLAG_DIAG44	(1UL << 5)