bnxt_en: Define macros for the various health register states.

Define macros to check for the various states in the lower 16 bits of
the health register.  Replace the C code that checks for these values
with the newly defined macros.

Reviewed-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>