Extend the FreeBSD OFED build framework to include the Broadcom bnxtre RDMA
provider library.
This change:
- Registers libbnxtre in src.libnames.mk so it is built and installed
as part of the OFED libraries.
- Adds bnxtre to the OFED pcap dependency set when MK_OFED is enabled.
- Declares proper dependency mappings for bnxtre (ibverbs, pthread).
- Introduces LIBBNXTREDIR for consistent object directory handling.
- Updates libibverbs and librdmacm build rules to link against libbnxtre,
enabling Broadcom RoCE device support at runtime.
- libbnxtre library uses below constructor to register with the libibverbs,
static __attribute__((constructor)) void bnxt_re_register_driver(void)
These updates ensure that applications using libibverbs and librdmacm can discover
and use Broadcom bnxt RDMA devices on FreeBSD.