drivers/staging/lustre: Nuke another unsigned >= 0 assert

drivers/staging/lustre: Nuke another unsigned >= 0 assert

Clean up another case of the compiler remininding the programmer they
are an idiot:

drivers/staging/lustre/lustre/ptlrpc/sec_bulk.c:308:34: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]
  LASSERT(page_pools.epp_waitqlen >= 0);

Just lose the assert, and save a page of compiler spew.

Signed-off-by: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>