Improve sed portability

The behaviour of "sed" on an incomplete line is unspecified by POSIX, and
On Solaris it apparently fails to process input that doesn't end in a LF.

Consequently constructs like

  re=$(printf '%s' foo | sed -e 's/bar/BAR/g' $)

cause re to be set to the empty string. Such a construct is used in
git-submodule.sh.

Because the LF at the end of command output are stripped away by the
command substitution, it is a safe and sane change to add a LF at the end
of the printf format specifier.

Signed-off-by: Chris Ridd <chris.ridd@isode.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-submodule.sh

@@ -73,7 +73,7 @@ resolve_relative_url ()
 module_name()
 {
 	# Do we have "submodule.<something>.path = $1" defined in .gitmodules file?
-	re=$(printf '%s' "$1" | sed -e 's/[].[^$\\*]/\\&/g')
+	re=$(printf '%s\n' "$1" | sed -e 's/[].[^$\\*]/\\&/g')
 	name=$( git config -f .gitmodules --get-regexp '^submodule\..*\.path$' |
 		sed -n -e 's|^submodule\.\(.*\)\.path '"$re"'$|\1|p' )
        test -z "$name" &&