RFR: JDK-8171249: modules_legal from imported modules are not read by the build

[Erik Joelsson]

Hello,

Please review this small fix following up JDK-8169925. That change 
forgot to add AC_SUBST for the new import modules variables. By adding 
those I have verified that modules_legal from imported modules are 
linked into the images.

Bug: https://bugs.openjdk.java.net/browse/JDK-8171249

Patch:

diff -r b6d3b5ea3a97 common/autoconf/source-dirs.m4
--- a/common/autoconf/source-dirs.m4
+++ b/common/autoconf/source-dirs.m4
@@ -128,6 +128,8 @@
    AC_SUBST(IMPORT_MODULES_CMDS)
    AC_SUBST(IMPORT_MODULES_LIBS)
    AC_SUBST(IMPORT_MODULES_CONF)
+  AC_SUBST(IMPORT_MODULES_LEGAL)
+  AC_SUBST(IMPORT_MODULES_MAN)
    AC_SUBST(IMPORT_MODULES_SRC)
    AC_SUBST(IMPORT_MODULES_MAKE)
  ])


/Erik