s390: delete unneeded #include <linux/kconfig.h> from facilities_src.h

The header facilities_src.h is only included from gen_facilities.c
and the tool is compiled with the following extra options:

    HOSTCFLAGS_gen_facilities.o += -Wall $(LINUXINCLUDE)

Please note $(LINUXINCLUDE) is expanded into build options including:

    -include $(srctree)/include/linux/kconfig.h

So, the Makefile always forces the tool to include kconfig.h, i.e.,
the #include <linux/kconfig.h> directive in the header is redundant.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/include/asm/facilities_src.h

@@ -6,8 +6,6 @@
 #error "This file can only be included by gen_facilities.c"
 #endif
 
-#include <linux/kconfig.h>
-
 struct facility_def {
 	char *name;
 	int *bits;