[TG3]: add bcm5752 entry to pci_ids.h

Add proper entry for bcm5752 PCI ID to pci_ids.h, and use it in tg3.
I did this separately in case patches like this (i.e. new PCI IDs)
need to come from more "official" sources.

Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>