profile: include full hostname in shell prompt

All of our devices are routers. Because they all serve the same purpose,
it is quite common that the first part of the hostname is the same for
multiple devices, and the location of the device is only included in
subsequent parts of the hostname.

Include the full hostname in the shell prompt, so it is easier to
determine the devices location.

Signed-off-by: Fabian Bläse <fabian@blaese.de>

bsp/default/root_file_system/etc/profile

@@ -26,4 +26,4 @@ alias ls='ls --color=auto'
 alias ip='ip --color=auto'
 
 # and color my prompt
-export PS1='\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '
+export PS1='\[\033[01;32m\]\u@\H\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '