make dist does not package all files required for compilation

[rski]

make dist results in an incomplete archive that is not suitable for building, resulting in errors such as

sh-4.2# make
         |make  all-recursive
         |make[1]: Entering directory `/tmp/zrpcd/extr/zrpcd-0.2'
         |Making all in zrpcd
         |make[2]: Entering directory `/tmp/zrpcd/extr/zrpcd-0.2/zrpcd'
         |  CC       zrpcd.o
         |In file included from zrpcd.c:14:0:
         |../zrpcd/zrpc_vpnservice.h:11:35: fatal error: zrpcd/zrpc_os_wrapper.h: No such file or directory
         | #include "zrpcd/zrpc_os_wrapper.h"

make works on the tree that was make disted to build the archive