git-quiltimport: preserve standard input to be able to read user input

When run without --author and it fails to determine an author, git
quiltimport tries `read patch_author` to get user input, but standard
input has been redirected to the patch series file.  This commit lets
quiltimport read the series file through file descriptor 3 so that the
standard input is preserved.

Reported by Uwe Kleine-König through http://bugs.debian.org/515910

Signed-off-by: Gerrit Pape <pape@smarden.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-quiltimport.sh

@@ -63,7 +63,7 @@ tmp_info="$tmp_dir/info"
 commit=$(git rev-parse HEAD)
 
 mkdir $tmp_dir || exit 2
-while read patch_name level garbage
+while read patch_name level garbage <&3
 do
 	case "$patch_name" in ''|'#'*) continue;; esac
 	case "$level" in
@@ -134,5 +134,5 @@ do
 		commit=$( (echo "$SUBJECT"; echo; cat "$tmp_msg") | git commit-tree $tree -p $commit) &&
 		git update-ref -m "quiltimport: $patch_name" HEAD $commit || exit 4
 	fi
-done <"$QUILT_PATCHES/series"
+done 3<"$QUILT_PATCHES/series"
 rm -rf $tmp_dir || exit 5