[E2FSPROGS, PATCH] Fix "make docs" rule in Makefile for doc folder.

["Manish Katiyar" <mkatiyar@gmail.com>]

On systems which don't have makeinfo installed by default, "make" or
"make docs" fails with the following error
/home/mkatiyar/e2fs-git> make docs
make[1]: Entering directory `/home/mkatiyar/e2fs-git/doc'
        MAKEINFO libext2fs.info
make[1]: makeinfo: Command not found
make[1]: [libext2fs.info] Error 127 (ignored)

This patch makes it to bail out with proper error message when
makeinfo is not present.

============================================================================
Signed-off-by: Manish Katiyar <mkatiyar@gmail.com>

diff --git a/configure.in b/configure.in
index 5243549..e64d817 100644
--- a/configure.in
+++ b/configure.in
@@ -595,6 +595,20 @@ AC_PATH_PROG(LDCONFIG, ldconfig, :)
 AC_CHECK_TOOL(AR, ar, ar)
 AC_CHECK_TOOL(RANLIB, ranlib, :)
 AC_CHECK_TOOL(STRIP, strip, :)
+AC_CHECK_PROG(MAKEINFO, makeinfo, makeinfo, )
+if test "_$MAKEINFO" = "_"; then
+    MAKEINFO="@echo Makeinfo is missing. Info documentation will not
be built.;true"
+else
+    case "$MAKEINFO" in
+      */missing.*)
+        AC_MSG_WARN([
+*** Makeinfo is missing. Info documentation will not be built.])
+        ;;
+      *)
+        ;;
+    esac
+fi
+AC_SUBST(MAKEINFO)
 AC_PROG_INSTALL
 # See if we need a separate native compiler.
 if test $cross_compiling = no; then
diff --git a/doc/Makefile.in b/doc/Makefile.in
index 5494cf0..9c961f3 100644
--- a/doc/Makefile.in
+++ b/doc/Makefile.in
@@ -13,7 +13,7 @@ INSTALL = @INSTALL@

 DVI=texi2dvi
 DVIPS=dvips -o "$@"
-INFO=makeinfo
+INFO=@MAKEINFO@
 HTML=texi2html

 all:: libext2fs.info libext2fs.dvi
======================================================================================

-- 
Thanks & Regards,
********************************************
Manish Katiyar ( http://mkatiyar.googlepages.com )
3rd Floor, Fair Winds Block
EGL Software Park
Off Intermediate Ring Road
Bangalore 560071, India
***********************************************