[contrib] Update qemu documentation

contrib/bochs/README.qemu

-Running Etherboot within qemu
-=============================
+Running gPXE within qemu
+========================
 
 Michael Brown <mbrown@fensystems.co.uk>
 
       make
 
 2.  Get the qemu source code:
-      cvs -d:pserver:anonymous@cvs.savannah.nongnu.org:/sources/qemu \
-           login
-      cvs -d:pserver:anonymous@cvs.savannah.nongnu.org:/sources/qemu \
-           co qemu
+      svn co svn://svn.savannah.nongnu.org/qemu/trunk qemu
 
 2a. Patch the qemu code.  There is currently a bug that causes qemu to
-    execute Etherboot incredibly slowly.  The bug seems to be related
+    execute gPXE incredibly slowly.  The bug seems to be related
     to the relative prioritisation of CPU and I/O operations within
     qemu.  This patch (which I found via Google) isn't a proper fix,
     but it does work around the problem:
 
 3.  Configure qemu with
       pushd qemu
-      ./configure --enable-system
+      ./configure --target-list=i386-softmmu,x86_64-softmmu
       popd
 
-    Note that qemu will not compile with gcc4; if your system's
-    default compiler is gcc4 then specify the path to gcc3 using
-    e.g. --cc=gcc-3.3.6
-
 4.  Build qemu:
       make -C qemu
 
         range dynamic-bootp 10.254.254.1 10.254.254.1;
       }
     You will also need to add in any of your usual declarations for
-    Etherboot, e.g. 'filename "vmlinuz.ltsp";'.  Note that this setup
+    gPXE, e.g. 'filename "vmlinuz.ltsp";'.  Note that this setup
     assumes that your DHCP server, TFTP server etc. all live on the
     machine you are using for running qemu.  If not, then you're on
     your own.
 7.  As root, restart dhcpd
       /etc/init.d/dhcpd restart
 
-8.  Build Etherboot floppy disk images and pad to 1.44MB
+8.  Build gPXE floppy disk images and pad to 1.44MB
       pushd ../../src
       make bin/rtl8139.pdsk
       popd
 			       -net nic,model=rtl8139 -net tap,ifname=tap0 \
 			       -boot a -fda ../../src/bin/rtl8139.pdsk 
 
-You should see qemu start up, load up Etherboot and attempt to boot
-from the network.
+You should see qemu start up, load up gPXE and attempt to boot from
+the network.
 
 
 
 ==============
 
 You can use the program "serial-console" to obtain a virtual serial
-console for Etherboot running within qemu.  Run "./serial-console" on
-a spare tty (e.g. a separate xterm window) before starting qemu, and
+console for gPXE running within qemu.  Run "./serial-console" on a
+spare tty (e.g. a separate xterm window) before starting qemu, and
 ensure that you have enabled CONSOLE_SERIAL in config.h.
 
 When serial-console starts, it will print out the message "Slave pty