Show libsubid api version in subid.h

Signed-off-by: Serge Hallyn <serge@hallyn.com>

.gitignore

@@ -48,3 +48,4 @@ Makefile.in
 /shadow.spec
 /shadow-*.tar.*
 /libmisc/getdate.c
+/libsubid/subid.h

configure.ac

@@ -741,6 +741,7 @@ AC_CONFIG_FILES([
 	libmisc/Makefile
 	lib/Makefile
 	libsubid/Makefile
+	libsubid/subid.h
 	src/Makefile
 	contrib/Makefile
 	etc/Makefile

libsubid/subid.h.in

@@ -4,6 +4,10 @@
 
 #ifndef SUBID_RANGE_DEFINED
 #define SUBID_RANGE_DEFINED 1
+#define SUBID_ABI_VERSION @LIBSUBID_ABI_MAJOR@.@LIBSUBID_ABI_MINOR@.@LIBSUBID_ABI_MICRO@
+#define SUBID_ABI_MAJOR @LIBSUBID_ABI_MAJOR@
+#define SUBID_ABI_MINOR @LIBSUBID_ABI_MINOR@
+#define SUBID_ABI_MICRO @LIBSUBID_ABI_MICRO@
 
 /* subid_range is just a starting point and size of a range */
 struct subid_range {