Staging: silicom: remove the EXPORT_SYMBOL_NOVERS macro

Since all references to EXPORT_SYMBOL_NOVERS have been removed,
we can remove its definition from bp_mod.h and bypasslib/bplibk.h.

Signed-off-by: Chad Williamson <chad@dahc.us>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>