(include_HEADERS): Mention include/unwind.h.

(Logical change 1.135)
diff --git a/Makefile.am b/Makefile.am
index 26cbda4..373d004 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -16,7 +16,8 @@
 if REMOTE_ONLY
   include_HEADERS = $(include_HEADERS_common)
 else
-  include_HEADERS = $(include_HEADERS_common) include/libunwind.h
+  include_HEADERS = $(include_HEADERS_common) include/libunwind.h \
+		    include/unwind.h
 endif
 
 SUBDIRS = src tests doc