manpage-bold-literal.xsl: stop using git.docbook.backslash

We used to assign git.docbook.backslash one of two different values --
one "normal" and one for working around a problem with docbook-xsl 1.72.
After the previous commit, we don't support that version anymore and
always use the "normal" value, a literal backslash.

Just explicitly use a backslash instead of using git.docbook.backslash.
The next commit will drop the definition of git.docbook.backslash
entirely.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/manpage-bold-literal.xsl

@@ -8,11 +8,9 @@
      this makes literal text easier to distinguish in manpages
      viewed on a tty -->
 <xsl:template match="literal|d:literal">
-	<xsl:value-of select="$git.docbook.backslash"/>
-	<xsl:text>fB</xsl:text>
+	<xsl:text>\fB</xsl:text>
 	<xsl:apply-templates/>
-	<xsl:value-of select="$git.docbook.backslash"/>
-	<xsl:text>fR</xsl:text>
+	<xsl:text>\fR</xsl:text>
 </xsl:template>
 
 </xsl:stylesheet>