s390/ipl: move ipl_flags to ipl.c

ipl_flags and corresponding enum are not used outside of ipl.c and will
be reworked in later commits.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/include/asm/ipl.h

@@ -83,11 +83,6 @@ struct ipl_parameter_block {
 	} ipl_info;
 } __packed __aligned(PAGE_SIZE);
 
-/*
- * IPL validity flags
- */
-extern u32 ipl_flags;
-
 struct save_area;
 struct save_area * __init save_area_alloc(bool is_boot_cpu);
 struct save_area * __init save_area_boot_cpu(void);
@@ -102,11 +97,6 @@ extern void ipl_update_parameters(void);
 extern size_t append_ipl_vmparm(char *, size_t);
 extern size_t append_ipl_scpdata(char *, size_t);
 
-enum {
-	IPL_DEVNO_VALID		= 1,
-	IPL_PARMBLOCK_VALID	= 2,
-};
-
 enum ipl_type {
 	IPL_TYPE_UNKNOWN	= 1,
 	IPL_TYPE_CCW		= 2,

arch/s390/kernel/ipl.c

@@ -119,7 +119,15 @@ static char *dump_type_str(enum dump_type type)
 	}
 }
 
-u32 ipl_flags;
+enum {
+	IPL_DEVNO_VALID		= 1,
+	IPL_PARMBLOCK_VALID	= 2,
+};
+
+/*
+ * IPL validity flags
+ */
+static u32 ipl_flags;
 
 enum ipl_method {
 	REIPL_METHOD_CCW_CIO,