byteorder: provide swabb.h generically in asm/byteorder.h

This is needed during the transition to the new byteorder headers as the
swabb.h functionality will be provided from asm/byteorder.h in the new
version.  To avoid breakage on arches still using the old implementation,
provide swabb.h from asm/byteorder.h as well.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/byteorder/Kbuild b/include/linux/byteorder/Kbuild
index 1133d5f..fbaa7f9 100644
--- a/include/linux/byteorder/Kbuild
+++ b/include/linux/byteorder/Kbuild
@@ -1,3 +1,4 @@
 unifdef-y += big_endian.h
 unifdef-y += little_endian.h
 unifdef-y += swab.h
+unifdef-y += swabb.h