[S390] initrd: change default load address

Change default load address of the initrd in case of IPL from reader.
The new load address is directly behind the kernel image.
This way we can see immediatly if there are any problems with the code
which tries to rescue the initrd in case the bootmem bitmap would
overlap with the initrd.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/kernel/head.S

@@ -366,7 +366,7 @@ iplstart:
 	l	%r1,.Lstartup
 	br	%r1
 
-.Linitrd:.long _end + 0x400000		# default address of initrd
+.Linitrd:.long _end			# default address of initrd
 .Lparm:	.long  PARMAREA
 .Lstartup: .long startup
 .Lreset:.byte	0xc3,0xc8,0xc1,0xd5,0xc7,0xc5,0x40,0xd9,0xc4,0xd9,0x40