cr-show.c: fix printf format warnings

cr-show.c: In function ‘show_pipes’:
cr-show.c:119:3: error: format ‘%8lx’ expects type ‘long unsigned int’, but argument 2 has type ‘u32’
cr-show.c:119:3: error: format ‘%8lx’ expects type ‘long unsigned int’, but argument 3 has type ‘u32’
cr-show.c:119:3: error: format ‘%8lx’ expects type ‘long unsigned int’, but argument 4 has type ‘u32’
cr-show.c:119:3: error: format ‘%8lx’ expects type ‘long unsigned int’, but argument 5 has type ‘u32’

Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>