Update the Makefile snippet which builds boot2

svn path=/head/; revision=41681

en_US.ISO8859-1/books/arch-handbook/boot/chapter.xml

@@ -308,9 +308,9 @@ Timecounter "i8254"  frequency 1193182 Hz</screen></para></entry>
       way:</para>
 
     <programlisting><filename>sys/boot/i386/boot2/Makefile:</filename>
-boot2: boot2.ldr boot2.bin ${BTX}/btx/btx
-	btxld -v -E ${ORG2} -f bin -b ${BTX}/btx/btx -l boot2.ldr \
-		-o boot2.ld -P 1 boot2.bin</programlisting>
+boot2.ld: boot2.ldr boot2.bin ${BTXKERN}
+  btxld -v -E ${ORG2} -f bin -b ${BTXKERN} -l boot2.ldr \
+    -o ${.TARGET} -P 1 boot2.bin</programlisting>
 
     <indexterm><primary>BTX</primary></indexterm>
     <para>This Makefile snippet shows that &man.btxld.8; is used to