tmac/doc.tmac: Call `ec' before mapping characters.

Resolves: #665535
Upstream: http://lists.gnu.org/archive/html/groff-commit/2009-04/msg00000.html

diff -uNPrp groff-1.20.1/tmac/doc.tmac groff-1.20.1/tmac/doc.tmac
--- groff-1.20.1/tmac/doc.tmac	2009-01-09 15:25:52.000000000 +0100
+++ groff-1.20.1/tmac/doc.tmac	2011-01-21 17:44:29.199598336 +0100
@@ -6425,6 +6425,9 @@
 .blm doc-empty-line
 .
 .
+.ec
+.
+.
 .\" For UTF-8, map some characters conservatively for the sake
 .\" of easy cut and paste.
 .
@@ -6438,9 +6441,6 @@
 .\}
 .
 .
-.ec
-.
-.
 .\" load local modifications
 .mso mdoc.local
 .