uml: Fix sample command line

Provide paths that match where LEDE is staging images.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

target/linux/uml/README

@@ -1,4 +1,4 @@
-Openwrt inside a user mode linux.  Why would we even want this many ask?
+LEDE inside a user mode linux.  Why would we even want this many ask?
 
 There are potentially a lot of reasons, one obvious one to me, it allows
 folks to 'kick the tires' without actually flashing up any hardware.  It's
@@ -17,7 +17,7 @@ build it all
 In your bin directory you will find a kernel and an ext4 root file system
 when it's finished.  Just run it like this:-
 
-bin/uml/openwrt-uml-vmlinux ubd0=bin/uml/openwrt-uml-ext4.img
+bin/targets/uml/generic/lede-uml-vmlinux ubd0=bin/targets/uml/generic/lede-uml-ext4.img
 
 The uml will start, and eventually the serial console of the uml will be at your
 console prompt.  If you would like it in xterms, substitute con=xterm and con0=xterm.