zdump: Don't use god-like C headers

Get rid of C headers which include everything. This is bad for testing and
maintainability. C files should include only what they need and no more.

Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>

zdump/dfi_kdump.c

@@ -9,7 +9,11 @@
  * it under the terms of the MIT license. See LICENSE for details.
  */
 
+#include <errno.h>
+
 #include "zgetdump.h"
+#include "zg.h"
+#include "dfi.h"
 
 struct df_kdump_hdr {
 	char			signature[8];