get rid of generic instances of asm/exec.h

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/arch/h8300/include/asm/Kbuild b/arch/h8300/include/asm/Kbuild
index c68e168..3a2af1a 100644
--- a/arch/h8300/include/asm/Kbuild
+++ b/arch/h8300/include/asm/Kbuild
@@ -1 +1,2 @@
 include include/asm-generic/Kbuild.asm
+generic-y += exec.h