git-format-patch: Always add a blank line between headers and body.

If the second line of the commit message isn't empty, git-format-patch
needs to add an empty line in order to generate a properly formatted
mail. Otherwise git-rebase drops the rest of the commit message.

Signed-off-by: Alexandre Julliard <julliard@winehq.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

git-format-patch.sh

@@ -174,7 +174,7 @@ titleScript='
 process_one () {
 	perl -w -e '
 my ($keep_subject, $num, $signoff, $commsg) = @ARGV;
-my ($signoff_pattern, $done_header, $done_subject, $signoff_seen,
+my ($signoff_pattern, $done_header, $done_subject, $done_separator, $signoff_seen,
     $last_was_signoff);
 
 if ($signoff) {
@@ -228,6 +228,11 @@ while (<FH>) {
 	$done_subject = 1;
 	next;
     }
+    unless ($done_separator) {
+        print "\n";
+        $done_separator = 1;
+        next if (/^$/);
+    }
 
     $last_was_signoff = 0;
     if (/Signed-off-by:/i) {