s390/boot: move EP_OFFSET and EP_STRING to head.S

Both macros are used only in decompressor's head.S, unnecessary to put
them in a global header used in many places like setup.h is.
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

arch/s390/boot/head.S

@@ -31,6 +31,9 @@
 
 #define ARCH_OFFSET	4
 
+#define EP_OFFSET	0x10008
+#define EP_STRING	"S390EP"
+
 __HEAD
 
 #define IPL_BS	0x730

arch/s390/include/asm/setup.h

@@ -10,8 +10,6 @@
 #include <uapi/asm/setup.h>
 #include <linux/build_bug.h>
 
-#define EP_OFFSET		0x10008
-#define EP_STRING		"S390EP"
 #define PARMAREA		0x10400
 #define HEAD_END		0x11000